Thursday, November 30, 2006
Every November, a common discussion arises involving the relationship of turkey and drowsiness. Here is the scientific explanation. Turkey happens to be high in an amino acid (a building block of protein) called tryptophan, which acts as a precursor to the neurotransmitter serotonin. As tryptophan crosses the blood-brain barrier, it is converted to serotonin with the assistance of the vitamins B6, B12 and folate. And, as serotonin levels increase, your food cravings are curbed, your mood improves and the feeling of sleepiness sets in.
Can the food you eat cause drowsiness? Of course! BUT do not blame the poor bird. Even though turkey does supply your body with tryptophan, your sleepiness is more likely the result of feasting on ample servings of stuffing, gravy, bread, rich side dishes and of course dessert! Next year resolve to eat less and leave the table for a little turkey trot. You will be glad that you did.
Friday, November 17, 2006
"For the past ten years, we've sought genes that confer longevity," Leonard Guarente, a professor of biology at Massachusetts Institute of Technology in Cambridge, told Reuters Health.
A gene that codes for the protein Sir2 appears to be one of them. In experiments with yeast, researchers have previously found that removing Sir2 from cells shortens their life spans, but adding an extra copy of the gene produces "superlong" cell lives, Guarente said.
Now he and his MIT colleagues have found in studies with yeast and mice that Sir2's activity seems to depend upon metabolism. They report their findings in the current issue of the journal Nature.
Sir2, explained Guarente, performs the necessary function of "silencing" genes, that is, it selectively turns off gene expression. All body cells contain the same DNA, yet these cells serve diverse purposes. A cell's identity -- for example, whether it's a blood cell or a skin cell -- depends on gene expression, Guarente noted. Some genes, he said, "need to be silenced, and some need to be active."
To their surprise, though, Guarente and his colleagues discovered that to do its job, Sir2 depends on a molecule known as nicotinamide adenine dinucleotide, or NAD. Present in all cells, NAD assists in breaking down food and aids metabolism.
This first coupling of metabolism and Sir2 is "incredibly exciting," Guarente said, because it could open up new avenues for slowing down the aging process.
"One of the few universals we know about aging is that calorie restriction can extend life," he noted.
This research offers an explanation: Cutting calories slows metabolism, which, Guarente said, may free up more NAD. In turn, the greater availability of NAD would keep Sir2 working properly. Moreover, keeping Sir2 in good shape should help keep the balance of silent and active genes in check, promoting the health of all body cells.
If further animal studies support this, the findings could do more than bolster the virtues of a lower-calorie diet, according to Guarente. Sir2 could become a drug target for preventing some of the degenerative diseases that come with aging, he said. A drug that, for example, binds with Sir2 and keeps it active may help protect bone and muscle mass from wearing down.
If such a drug is realized, however, it won't tack years onto anyone's life. Guarente said a Sir2-targeting drug would make little difference in longevity, but instead could help people "maintain their vitality longer."
Dr. Kevin M. Guskiewicz and his colleagues attribute this increased risk to the failure of clinicians to follow recommended return-to-play guidelines.
The researchers collected data from 242 high school and collegiate athletic trainers. Of 17,549 players, 5.1% sustained at least one concussion, and 14.7% of these sustained a second concussion during the same season. The second injury tended to be more severe.
The investigators report that 86% of concussed players reported headache, 67% reported dizziness, and 59% reported confusion. Headache persisted beyond 5 days in 10% of the injured players.
Although most grading scales are based on loss of consciousness and amnesia, in this study only 8.9% of those injured lost consciousness and 27.7% exhibited amnesia.
"Clinicians are usually forced to make decisions based on grading scales and return-to-play guidelines that are not inclusive of the most common signs and symptoms," Guskiewicz's group writes in the September-October issue of the American Journal of Sports Medicine.
Nearly a third of injured players returned to participation on the same day of injury, including 14.4% of those who sustained a grade II concussion. For the remainder of the injured players, return to play averaged nearly 3 days earlier than most of the recommended guidelines, the investigators note.
Guskiewicz and his associates conclude that "few clinicians are currently using assessment techniques...useful in identifying lingering signs and symptoms such as concentration deficits, blurred vision, (sensitivity to light), amnesia, dizziness and balance deficits."
Western science and medicine, heavily influenced by Cartesian philosophy, which makes a sharp distinction between mind and body, observer and observed, subject and object, has focused mainly on external causes and treatments for disease. Descartes’ most famous statement, “I think, therefore I am,” announces the basis of his philosophy and science, in which he views the outside world (the human body included) as a clockwork mechanism that can be objectively broken down into its component parts. The mind, in this view, is autonomous, neither altering the universe by observation, nor being altered by its interaction with its environment. Western science has largely adhered to this outlook, and has made tremendous progress in understanding the universe in which we live. In the last few decades, limitations have been recognized in sciences such as quantum physics, with the discovery that the role of the observer is not clearly distinct from the phenomenon being observed, and in medicine, where it is becoming clear that the mind and body cannot be so easily divided.
While many of the tenets of traditional medicine can be taken as philosophical or metaphorical, instead of scientific, there is evidence the balance between the mind and body that these ancient systems prescribe has a basis in modern Western medicine, in a balance between the brain and the immune system.
The body responds to stress by releasing hormones and other chemical agents that alter physiological processes in order to deal with the stressful situation. This biochemical/physiological process is known as the stress response. One key hormone in the stress response is cortico-releasing hormone (CRH). This hormone is released mainly by the hypothalamus in the brain, and, through a cascade of chemical events, leads to the release of cortisol by the adrenal glands. Cortisol causes elevation in heart rate, increased strength of heart contractions, and an array of other physiological events. Cortisol also seems to act as an important regulator of the immune system and as an anti-inflammatory agent. It plays a key role in keeping the immune system from over-reacting and damaging healthy tissues. Studies have also shown that white blood cells within the immune system produce molecules—called cytokines—that send signals to other parts of the immune system, and also to the brain. The brain then responds by inducing some of the behaviors associated with the stress response such as anxiety, and also the behaviors often associated with sickness such as lethargy and fatigue. Cortisol also has an inhibitory effect on the production of CRH, working in a feedback loop to shut off its own production.
Thus, through these chemical processes the brain and the immune system communicate and interact in order to regulate the body’s responses to stress, both external and internal. If this system is somehow altered or interrupted, miscommunications can occur and the body may respond improperly. For instance, continuous stress results in overproduction of cortisol, which in turn has a negative effect on the immune system, and may potentially lead to higher susceptibility to infection and disease.
Improper regulation of the stress response is associated with a number of conditions affecting the brain. For instance, people with classic depression have been shown to have high levels of cortisol in the blood. Depressed patients can often exhibit symptoms of the physiological stress response, such as anxiety and sleeplessness. Some studies have shown a correlation between the high level of cortisol and suppressed immune responses, but further study is needed to confirm these results. Also, patients who suffer from “atypical” depression often exhibit a reduced stress response and have impaired CRH production, which leads to fatigue and lethargy. Sufferers of seasonal affective disorder (SAD) also exhibit some of these symptoms. Chronic stress has also been shown to have other negative effects on brain function, such as impairment of learning and memory. Also, as mentioned above, stress, acting through the brain and immune system, has an effect on inflammatory responses in some diseases, such as arthritis. Stress can affect the level of inflammation, and thus the pain, associated with disease. The details of all the biochemical and physiological processes involved are far from worked out, but scientists are continuing research on the chemical pathways and interactions that take place between the brain and the immune system.
At the level of medical treatment, work is being done with several therapeutic techniques that integrate stress reduction and mind/body interaction. Traditional meditation techniques have been used to successfully reduce stress, high blood pressure, and chronic pain. It has helped Vietnam veterans deal with the effects of post-traumatic stress syndrome and may help reduce serum cholesterol levels and ease the struggle with substance abuse.
Guided imagery is a related technique in which the patient’s imagination is brought into play by using imagery and other imagined sensory experience to alter physiological processes. It has been used successfully to control pain and enhance immunity.
Biofeedback is a procedure that combines methods of relaxation and meditation with high-tech monitoring. A patient’s physiological functions are monitored, providing immediate feedback showing the effect of any relaxation techniques being practiced. Patients can learn to control heart rate, body temperature and brain wave activity, among other things. The use of monitoring devices lets the patients see the results of their thinking and mental efforts at controlling these physiological functions, and allows them to adjust their efforts accordingly to reach the maximum desired effect. With practice, a patient can learn to achieve the desired effect without the use of the monitoring devices. Biofeedback is used in the treatment of many disorders, including stress, high blood pressure, pain, epilepsy and sleep disorders.
Other therapies that aim to integrate body and mind and/or use the power of the mind to help treat illness include support groups, which have been shown to be highly successful in helping breast cancer patients confront their disease; yoga; art and dance therapy, which help patients express concerns and emotions and feelings related to their illness and to help improve self-image and self-understanding; music therapy; and hypnosis. This list is far from complete and many more new techniques and uses for the therapies listed here are being studied and developed.
There is still a long way to go and much left to learn, both at the biological level and at level of medical treatment, about the interactions of the mind and body. Many medical institutions have created centers to study and utilize alternative types of therapy, including therapies intended to bring the mind and body into balance and to use the power of the mind to aid in healing and recovery. The National Center for Complementary and Alternative Medicine (NCCAM), part of the National Institute of Health, conducts and supports research on a wide variety of alternative treatments. Many feel that the wisdom of traditional medicine is largely in its recognition of the importance of balance within the mind and body. Modern medicine is recognizing some of the benefits of mind/body interactions, and the balance of traditional and modern techniques may lead to treatments that neither system alone could achieve.
American Psychological Association. Rallying the troops inside our bodies.
Available at: http://helping.apa.org/mind_body/pnia.html
Association for Applied Psychophysiology and Biofeedback Website. Available at: http://www.AAPB.org
Damasio AR. Descartes’ Error. New York: Avon Books; 1994: 223-267.
Sternberg EM. Emotions and disease: From balance of humors to balance of molecules. Nature Medicine. 1997;3(3):264-267.
Sternberg EM, Gold PW. The mind-body interaction in disease. Scientific American (special issue: Mysteries of the Mind). 1997;7(1):8-15.
Monday, November 13, 2006
It's true that memory slightly declines after age 30, but it usually doesn't become noticeably impaired until after age 75. Instead, memory problems seem to come to light in middle age because people tend to be more aware of their memory shortcomings when they need it the most -- at an age when they have more responsibilities and need to remember more.
On average, most people forget names or misplace items an average of once a week to once a month. They recheck something, such as checking to make sure they've turned off the stove or locked the door, about once a week.
If you're concerned about your memory, that's a good sign. If you had a real memory problem, you wouldn't remember that you couldn't remember. But here's how you can help ease your mind and get the most from your memory:
Try to stay calm. Being worried or anxious can temporarily impair your memory. Some people find their memories "freeze up" under stressful situations. The harder they try to remember, the worse their memory is. The trick is to relax and refocus your mind -- the memory usually returns.
Practice a healthy lifestyle. Eating a low-fat diet, exercising regularly and practicing other so-called "heart-smart" strategies helps to keep your arteries open and functioning optimally, so your brain will get a steady flow of blood to supply oxygen and nutrients. Regular exercise has been shown to improve some mental abilities by an average of 20 to 30%.
Monitor your senses. You can't remember something if you never learned it in the first place. If you're having trouble paying attention because of poor eyesight or poor hearing, see a doctor about getting glasses or a hearing aid.
Don't test yourself needlessly. You likely have enough to remember without testing yourself with trivial matters, and the act of remembering doesn't improve memory. Instead of trying to "cram," make lists, write yourself notes, keep a journal or diary of important facts and dates or tell a friend or spouse. Interestingly, the act of writing things down helps you remember, and having the list or a stack of Post-It notes will jog your memory.
Get into a routine. You'll have a better chance of remembering to do something if you do it the same way every day. Put your car keys in the same place; go through the same sequence of actions before you leave the house. After a while you'll be able to put yourself on automatic pilot for these simple tasks.
Rekindle your memories. When you need to remember something, try to make connections with already existing memories. It's easier for experts to learn a new fact in their field because they already have a framework of knowledge on which to hang the new piece of information. For names, try to connect the name to someone you know or a character in a movie or book. For example, if you meet a woman named Sandra, you might make a mental connection to your favorite actress, Sandra Bullock or Sandra Dee.
Barry Gordon, M.D., Ph.D., a Professor of Neurology and Cognitive Science at the School of Medicine and Director of the Memory Clinic at the Johns Hopkins Medical Institutions, is among the nation's foremost authorities on memory. He is author of Memory: Remembering and Forgetting in Everyday Life, available through amazon.com or barnesandnoble.com, or by calling 410-435-2865.
"The relief of pain remains a major challenge in modern medicine," says University College London’s Professor of Neuropharmacology, Anthony Dickenson. However, pain has proved to be remarkably difficult to tackle.
Pain is a very personal experience, partly because there is no truly objective way of measuring it. However, in the last decade scientists have gained a more thorough understanding of the mechanisms that trigger pain and the neural pathways that transmit pain signals to the brain, raising hopes for more effective treatment strategies in the future.
The pain pathway
Exposure to heat or damage to tissues stimulates C-fibers, a set of fine nerve fibers that run from the skin and other tissues to the spinal cord. Within the spinal cord, they form connections with other fibers in a structure called the dorsal horn. These fibers then carry the pain signals on to the brain. This route, from tissue through the spinal cord to the brain is called the pain pathway, and there are numerous ways of potentially blocking or disrupting it.
Blocking pain in the periphery
One possibility is preventing the C-fibers from being stimulated. All nerves conduct messages by allowing minute pores to open and close in their membranes. These pores regulate the flow of sodium ions in and out of the nerve fiber, allowing signals to pass along. Local anesthetics block these sodium channels, and if their action is blocked, the nerve can no longer transmit signals, including pain. However, local anesthetics have drawbacks. If they escape into the blood circulation, the anesthetics can block sodium channels in other areas, including the heart and brain.
C-fibers are triggered by excessive heat. "The issue is, why don’t C-fibers respond until the temperature is up to 42 degrees centigrade – an extreme temperature – why don’t they respond before?" asks Dickenson. The answer, he explains, is that C-fibers contain a specialized form of sodium channel that only opens at temperatures that are likely to cause damage. Working at University College London, Dr John Wood has thoroughly analyzed this channel. It has been isolated and genetically engineered into bacteria so that large quantities can be produced and studied. The race is now on to find a chemical that can block its action while leaving all other sodium channels unaffected. "How many companies are chasing this idea is anyone’s guess, but you can guarantee that they are," says Dickenson with a smile.
An interesting note: These channels also respond to capsacin, the hot component of chili peppers, which explains why a curry feels ‘hot’ rather than feeling like you are chewing glass.
Another approach to preventing C-fiber stimulation is to block the production of prostaglandin, a chemical released from a tissue as part of its inflammatory response to damage. One of its actions is to stimulate C-fibers. A group of drugs called non-steroidal painkillers blocks the action of the prostaglandin-producing cyclooxygenase enzymes COX1 and COX2. However, a major problem with these compounds is that they are indiscriminate in their action, and block the enzymes in locations like the blood vessels and stomach wall, where prostaglandins play an important role in maintaining healthy tissue. In blocking chronic pain, you can end up causing stomach ulcers.
However, there is renewed hope that this approach may work. It now appears that while COX1 is present in almost all tissues, COX2 is present in particularly high concentrations in damaged tissues. There are now some drugs that are capable of specifically blocking COX2.
Dickenson points out that COX2 is also constantly present in the brain, although no one is quite sure what function it has there. Its presence, though, could explain why non-steroidal painkillers like paracetamol, which can block COX2, are pretty good at inhibiting pain in situations like fever, even though they do nothing to reduce inflammation.
Dickenson comments that a big issue with new generations of painkillers will be their high price relative to the cost of drugs like aspirin and paracetamol.
Dealing with pain that results directly from injured nerves is also a major clinical problem. Most of the drugs that are showing signs of tackling this neuropathic pain were originally designed as anticonvulsants, antidepressants, and antiepileptics. Among the newcomers to the field, gabapentin appears to present the most hope. Its mode of action is unclear, but it probably operates by blocking calcium channels in the neurons, and clinical trials show that it can be quite effective. The sodium channel blockers discussed above could also be of great importance in treating neuropathic pain.
Blocking pain in the spinal cord
Yet another approach to blocking pain is to allow the C-fibers to become stimulated, but block the transmission of their signal within the dorsal horn of the spinal cord. The major neurotransmitter involved in this process is glutamate, and there are many pharmaceutical companies focussing on the task of blocking the N-methyl-D-aspartate (NMDA) receptor that glutamate binds to. The problem is that these drugs currently have many adverse side effects, such as sedation, so at the moment they are given as a last resort. However, there appear to be many sub-types of the receptor, raising the hope that it might be possible to block the NMDA receptors that mediate pain without inducing side effects.
Within the spinal cord, a peptide known as substance P plays an important role in transmitting pain signals from one neuron to another. Speaking at the Society for Neuroscience held in Miami in October 1999, Dr Ronald Wiley of Vanderbilt University and Veteran Affairs Medical Center, Nashville, explained that when substance P becomes attached to its receptor on the surface of a neuron, the receptor-substance P conjugate is drawn inside the cell. This has given a number of researchers the idea of attaching a toxin to substance P and injecting it alongside the pain pathway. The theory is that the toxin will be drawn only into fibers associated with transmitting pain and will selectively kill them. Work in laboratory animals indicates that this approach has a potentially powerful effect. Dickenson, however, is skeptical about any approach aimed at destroying elements of the nervous system in order to reduce pain. "The idea seems great," he says, "but prior to this modern wave of intervention in pain, surgeons used to treat chronic pain by cutting nerve tracts in the spinal cord - the pain went away for a bit and then returned with a vengeance. I’m not sure that these toxins will fare any better."
Blocking pain in the brain
Drugs acting in the periphery are useful because they don’t need to get into the central nervous system and so don’t cause side effects associated with central nervous system function. However, as we have seen there are multiple peripheral mechanisms that trigger pain, and you can only block one at a time. Drugs like the opioid morphine, which acts within the brain, can block all pain. "Opioid-like drugs have been around for at least three millennia and are arguably the most valuable drugs in medicine," claims Dickenson.
The trouble with opioids is their side effects of addiction, euphoria, and a reduced ability to think clearly. Opioids bind to receptors in the membranes of neurons and prevent the neurons from firing. Morphine works on the mu-receptor, but delta-receptors, kappa-receptors, and, more recently, opioid receptor-like 1 receptors (ORL1) have been discovered. The hope is that a drug will be developed that can bind to the correct ratio of the different types of opioid receptors so that it kills pain without inducing the adverse side effects of morphine. "At the moment it looks as though concentrating on the delta-receptors could provide the best way forward," says Dickenson.
The neurotransmitter serotonin (also known as 5-HT) is involved in some cases of migraine, and drugs that block its ability to bind to nerves are capable of blocking migraine-associated pain. This role of serotonin also explains why some people suffer from migraines after consuming red wine or chocolate, as both of these contain high quantities of chemicals that the body can turn into serotonin. It also explains why migraines are one of the potential side effects of specific serotonin re-uptake inhibitors (such as Prozac) used as antidepressants, as they allow the concentration of serotonin in the brain to increase.
Finally, cannabis may prove useful in the fight against pain. This compound stimulates two different receptors named cannabis 1 and cannabis 2, although it appears that cannabis 1 is the predominant receptor in the brain. Dickenson is keen to see the results of a number of Canadian trials that are testing to see if the drug operates predominantly through its mood altering properties or whether it really is a potent analgesic.
Pain plays a useful role in that it alerts us to damage to our bodies. Problems arise when the siren sounds too loud and for too long. The next few years should see new drugs that promise a more intelligent and directed approach to releasing hundreds of thousands of people from the captivity of being in pain.
In the most recent study, published in the October 15, 1999 issue of Science, researchers showed that new neurons are continually being added to the cerebral cortex of adult monkeys. The cerebral cortex is the largest and most complex region of the brain and is the seat of high-level decision-making, thinking, and personality.
The discovery, made by Elizabeth Gould and Charles Gross of Princeton’s Department of Psychology, along with graduate student Alison Reeves and research staff member Michael Graziano, is likely to translate to humans. Monkeys and humans, as fellow primates, have fundamentally similar brains.
Gould and Gross point out that it’s not yet known what purpose the new cells serve in the cortex, but if the newly formed neurons are found to have a functional role, scientists may have to re-examine current theories about how the brain works. For instance, it’s been known for some time that the adult brain displays a certain degree of plasticity, that is an ability to change, but traditional thought is that the brain handles processes like learning and memory by altering the nature of the connections, called synapses, between neurons. If new cells are being generated on a regular basis, a whole new level of complexity is opened up.
“We know that the brain is plastic and can change as a result of experience,” says Allan Tobin, director of the Brain Research Institute at UCLA, “but what we don’t know is whether these changes are mediated by pre-synaptic changes, post-synaptic changes, or now, by the generation of new cells.”
If the results are confirmed in humans, they could have major implications for the treatment of neurodegenerative diseases like Parkinson’s, Huntington’s, or Alzheimer’s disease. In these diseases neurons either die or lose their normal function. When a critical number of cells have been lost, symptoms arise and continue to worsen as more and more neurons are effected. While practical applications are years away, physicians may one day find ways to influence the process of neurogenesis in order to generate more neurons in a particular region of the brain.
“With the idea that new cells themselves can be generated in the adult brain,” says Tobin, “maybe you can find signals that will differentiate a whole cohort of cells to replace those that have died.”
Finding New Neurons:
In order to test for the presence of new neurons in the adult brain, Gould and Gross injected rhesus monkeys with a chemical called BrdU. Cells that are dividing incorporate BrdU into their DNA and pass it on to the newly formed cells. At different time points after the injection, ranging from two hours to seven days, the researchers examined the cerebral cortex and found evidence of BrdU containing cells in three different regions. Because BrdU is only incorporated into the DNA of cells that are actively dividing, the cells with DNA containing the chemical had to have formed after the injection.
The researchers conducted additional experiments to determine that these newly formed cells had the characteristics of neurons. They were able to detect several different proteins in the cells that are found specifically in neurons. Also, they showed that the cells containing BrdU had the long extensions, called axons, characteristic of neurons. To do this Gould and Gross used a technique called fluorescent retrograde tracing. In this technique a chemical dye is applied to a small region of the brain, and the dye travels from the end of the axon back to the cell body, making the axon visible under a microscope.
According to Gould and Gross, the new cells appeared to originate in a region called the subventricular zone (svz) and then migrated outward in a stream through the cerebral cortex to specific locations, where they differentiated into mature neurons. The svz was previously identified by other researchers as a source of neuronal stem cells—cells capable of dividing and differentiating into a variety of specialized brain cells.
The new cells were found in three of the four regions that were examined—the prefrontal region, the inferior temporal region, and the posterior parietal region. These three brain areas are involved in the complex cognitive tasks of decision making and short-term memory, recognition of objects and faces, and the representation of objects in space, respectively. No new cells were found in the striate cortex, which is responsible for the initial, basic steps of visual processing.
The observation that new cells were found in regions important for cognitive functioning and not in an area involved in more rudimentary processing suggests that neurogenesis may play a role in higher brain functions. Gould and Gross speculate that the new neurons could play a role in learning and memory by “marking the temporal dimension of memory” and serving as “a substrate for learning.” In a sense, the new neurons may be timekeepers, somehow helping keep memories in the right order and marking them in time. They could also be serving as a blank slate, on which new memories could be written and new skills learned.
A Brief History:
“It’s a surprise,” says Tobin of UCLA, referring to the Gould and Gross experiments, “but it’s a surprise that’s been growing on us for the last couple of years.”
In fact, evidence that neurogenesis occurs in the adult brains of some animals, such as rats and birds, has been around for many years. In 1965, Joseph Altman and his colleagues showed that new neurons were regularly produced by adult rats in the hippocampus, a region of the brain important for the early phases of learning and memory.
In the 1980’s Fernando Nottebohm, of Rockefeller University, discovered that songbirds, such as the canary, produced new neurons during the time they were learning new songs. This was particularly interesting work as it suggested that the production of new neurons was connected with a particular behavior. Nottebohm’s continuing research has shown that birds add new neurons to their hippocampal complexes throughout their lives.
Studies of neurogenesis in primates during the 1980s turned up only negative results, and it was perhaps because of these results that the study of neurogenesis in higher mammals remained largely unexplored until now.
In any case, more recent evidence of neurogenesis has been found in the hippocampi of adult primates, including humans. In 1998, Fred Gage of the Salk Institute for Biological Studies in La Jolla, California, and Peter Eriksson at the Sahlgrenska University Hospital in Goteborg, Sweden, looked at hippocampal tissue from five patients that had died of cancer. These cancer patients had received an earlier injection of BrdU for diagnostic purposes (since BrdU labels dividing cells, it can also help in the detection of growing cancer cells). Gage and Eriksson found BrdU labeled neurons in the hippocampi of all five patients, who ranged in age from 57 to 72 years old.
Still, it was unclear whether neurogenesis occurs in the higher parts of the brain like the cerebral cortex. Evolutionarily speaking, the hippocampus is a very old structure, present in brains from reptilian to human. The newer structures, such as the cerebral cortex were still thought to lack the ability to grow new neurons.
That’s where the new experiments by Gould and Gross come in. By showing that neurogenesis occurs in the cerebral cortex of primates, they have shown that the brain is a much more dynamic organ than previously believed. The next steps will include proving that similar results can be found in humans and discovering the functional role of the newly generated neurons.
Eriksson PS, Perfilieva E, Bjork-Eriksson T, Alborn AM, Nordborg C, Peterson DA, Gage FH. Neurogenesis in the adult human hippocampus. Nature Medicine. 1998;4(11):1313-1317.
Gould E, Reeves AJ, Graziano MSA, Gross CG. Neurogenesis in the neocortex of adult primates. Science. 1999;286:548-552.
Gould E, Tanapat P, Hastings NB, Shors TJ. Neurogenesis in adulthood: a possible role in learning. Trends Cog Sci. 1999;3(5):186-1992.
Monday, October 30, 2006
How can the fats be lowered and the tastes be maintained?
With some non-fat products, it is simply a matter of becoming accustomed to them. For example, after drinking only non-fat milk for several months, regular milk will seem too fatty, almost like cream. Some people claim to have lost the desire for the full-fat versions.
It may be helpful to gradually make the move to non-fat products. For example, blend 2% milk with non-fat, and slowly increase the amount of the non-fat milk. This can be done over several days or even weeks.
With cheese, the non-fat version does not melt like the fattier kinds. The answer? Using shredded cheese as an example, make the bulk of the cheese non-fat, but top it with a little regular cheese. The small amount of fat will help all the cheese melt.
In baking, fats are not necessary. Oil and eggs can be completely omitted. Texture and taste is not compromised by substituting applesauce, non-fat sour cream or prune puree, and they contain no fat! One caution; the non-fat margarine and butter spreads cannot be used successfully in baking.
For dishes such as scalloped potatoes, use non-fat milk and a product like "Butter Buds." The fat is gone, but the flavor remains!
Substituting one food item for another can also substantially lower fats in the diet. For example, by using jam or jelly instead of butter, toast becomes nearly fat-free. Eating chicken or fish instead of beef is another obvious way to lower fat intake. Topping vegetables with spices rather than creamy sauces is another fairly simple way to avoid fat.
Many commercial products now contain "olestra," a synthesized fat with molecules too large to be absorbed in the intestinal tract. Such foods as non-fat ice cream are satisfying or not depending upon the product and the person eating them, but olestra gives the creamy texture that once came only from fats.
Olestra is also used in potato chips. Some people claim they cannot tell the difference between the fat-free version and the full-fatted kind. The one drawback to eating foods containing olestra, is they may cause "intestinal distress," including excessive gas, bloating and diarrhea. There is also concern over olestra binding to fat-soluble vitamins and passing them out of the body, perhaps causing a vitamin deficiency in some people.
Here's a helpful hint
The trick to lowering fats in the diet is not to completely eliminate them. Some fat is necessary and healthy. The best way to keep fats under control is to substitute when possible, and keep in mind that moderation is the key.
Saturday, September 30, 2006
Online diets are perfect for people who don't have enough time in the day to join other weight-loss programs like Weight Watchers or Jenny Craig. And although most online diet sites require a monthly or yearly fee (generally between $50 and $100 for an entire year), they are still reasonably priced when you consider the cost of joining a non-Web-based weight-loss program or going to a nutritionist. In addition, because 95 percent of dieters will regain the lost weight within one to five years of going on a diet, individuals who try out cyber dieting have more than likely already attempted numerous diets like Weight Watchers or diets one can find in books, like "The Zone" or "Dr. Atkin's Diet Revolution." If they weren't successful on other diets the Internet might be just the thing that keeps them on track.
According to the Brown University study, the people who received online help filled out personal profiles or surveys, created online diaries to record their food consumption and physical activity. They were also given access to online bulletin boards so that they could share their thoughts and experiences with other participants.
An interesting note to point out: The dieters who received personal feedback and therapist or diet-expert support, showed greater amounts of weight loss than the participants who didn't have feedback. Some experts think that the virtual support groups are the key. Although online diets can be pretty simple and easy to follow, there is always a need to stay committed and motivated. With bulletin boards and round-the-clock help, the help is there when the dieter needs it.
Online diet programs also give users a great deal of privacy, so for people who are insecure about the amount of weight they need to lose or go into a panic when they know they have to step onto a scale at a face-to-face dieters' meeting, they might find dieting on the Web to be the ticket for keeping the diet personal and private. The Internet is also incredibly convenient - it's open 24/7! So a world of nutritional information, facts and advice, always is available.
Another huge advantage to online dieting is that there are diets ranging from high-protein, vegetarian, and because there are so many online diets to chose from, it's almost a given that any one specific person will find a diet that fits his or her own needs.
Although most of the data collected on online dieting is new, it seems like virtual dieting itself is here to stay. And with the positive results continuing to poor in, online dieting might be the answer all of us perfect-body seekers are looking for!
Women especially lose sight of what it really takes to lose body fat and tone muscles. They constantly try new diets. They routinely take pills, and they relentlessly cut calories-always looking for that one diet, eating plan or fitness fad to lose unwanted flab on the abdomen and arms.
Unfortunately, most women in their quest for a leaner, trimmer body actually make themselves a better fat-storer and highly inefficient calorie burner.
The solution? Weight training.
Just imagine your life without low-calorie dieting, taking pills and being consumed with a flatter stomach or trimmer thighs. Wouldn't it be great? It can be. You just have to pick up some weights or use machines either at home or in the gym, two to three times a week.
You see, as we age we lose muscle, and because we become less active and eat more calories, the fat builds up. So to lose the fat and put muscle back on your body, you have to challenge the muscle with a load. Weight training is the way.
Now this doesn't mean you have to spend hours in the gym or hours with your equipment at home. But it does mean you have to spend at least 30 to 40 minutes working out with weights, two to three times a week. Check out videos. Tune into ESPN fitness shows. Read magazines. Consult a fitness trainer or hire one. There are basic routines for working the major muscles groups that will strengthen and tone your body. By building muscle you increase the calorie burning.
A pound of fat burns two calories. A pound of muscle burns 35 to 50 calories. Now imagine eating more because you're a better fat burner.
So what do you do?
Perform two or three sets of 10-15 repetitions for each body part; workout on alternating days. Never work the same muscle group two days in a row. Your muscles need recovery time. So perform your weight workout Monday, Wednesday and Friday or Tuesday and Thursday or however it fits your lifestyle. The key is to be consistent, and this isn't something you do for a few weeks. It takes months to change your body.
Throw away the scale. It is not the best indication of how much fat or muscle you have on your body. More muscle on your body may mean for you a higher number on the scale. Take your measurements and have your body fat tested. But rest assured, as a woman you won't bulk up unless you're spending hours in the gym everyday and you are genetically predisposed to more muscle mass.
So, if you want to lose body fat, tone up, get stronger and look better in your clothes, you need to weight train. Stay consistent. Keep it up. You will win the battle of the bulge, once and for all.
Monday, September 25, 2006
Still, all those summer mornings which I spent heaving semi-clear suburban air as I pounded the pavement on warm, soothing mornings are but a memory for another year. Now, as I travel those same sidewalks each morning, I see very different sights, such as Halloween and Thanksgiving decorations, wilting flowers, bags of clippings, and most importantly, piles of leaves raked together by children. I can remember spending many an hour raking when I was little, trying to make the largest and widest pile that I could make, and all this work was for the sole purpose of jumping into it and feeling the good feeling of being a child buried three feet under crinkly autumn leaves. I was at peace with myself within these moments, and I enjoyed them immensely.
Almost fifteen years later, I am very proud to see that today's kids have taken up where I left off; they pile massive quantities of leaves. I thought I would be a mischievous runner and refamiliarize myself with the favorite activity of past Octobers. Most of the week, the majority of my run is spent in quiet residential blocks where many large trees still retain their majesty and, of course, their many leaves. There is one street nearby that has a particularly high density of large oaks, walnuts and maples, and it happens to be one of my most beautiful running routes.
Each fall, the trees become bare, but the streets become a sea of leaves, and the sidewalks a small mountain range of collected piles. This year, I thought I would rejoin my present with my past and go for another jump through the leaves. I set everything up perfectly in my mind, even going so far as to plan where I would park and which streets I would follow so that the leaves would be the grand finale of a great run.
When I got to the street, all the piles were there in formations familiar to my childhood, even though I grew up in a town miles away. All of them were inviting targets. I ran backwards several dozen meters in fact, just so that I could get up enough speed to get some really good jumps into my nice little destructive barrage, and once I reached a point where I felt comfortable starting from, I was off. When I came barreling into the first pile, there was a sensation unlike anything else I had felt in ages. I felt seven again, and in those seconds, weeks of memories returned to me.
The leaves flew up and fell back on me, I was sitting on the ground in the midst of the multi-colored haze, and I was smiling a rather large smile. I could have sat there for hours, yet there were several more leaf piles to torment. I was sure that people would blame it on the wind, for the leaf piles weren't my own. I didn't even know most of the people on the street, but I was experiencing way too much nostalgia to think as clear as I normally do.
The second pile was about twice as large and several hundred feet away. I got up, brushed myself off and stretched some, just to ensure that I could put 100% of Lorne into his next act of running mischief. I started slow, but gained speed at a steady pace so that I would be going full steam when I got to the pile. Seconds later, I was there and I jumped. It seemed that time stood still, as I was in the air heading for the leaves.
It was at this moment that I heard words which still ring out as clear as they did when I hit the ground: "What are you doing, sir?"
I was red-faced. This was perhaps the most embarrassing and awkward moment for me in recent memory, and being an experienced performer, I have had many embarrassing and awkward moments. The woman standing before me, looked at me as more of a pathetic figure than someone worth any amount of ire or anything even remotely resembling anger. I sat there, in her leaf pile, trying to compose a very succinct but cute way of explaining my presence in her yard. I stood up, calmly cleaned myself, and then proceeded to tell her how this was something I always loved to do when I was little and the temptation was simply too much and I had to do this once more for old times' sake and I would be glad to rake it back.
It was then that I heard words, which were said through laughing, so I knew that I probably did sound like a very pathetic person, even for a twenty-something freelance writer.
I heard : "Just run."
I ran off, refraining from risking the wrath of other people who might have more stringent objections to the presence of a runner in their leaves. I actually drove home and, before I started my several hours of writing for the day, tried to ascertain if there were enough leaves to make a pile that I could use for my own purposes.
So far, our trees have kept their leaves, but I will certainly be found outside soon, burying myself in the red and yellow mountains, which form beneath our large maple trees. The next day, I ran down another street that was full of leaves, but nobody had taken the time to rake them up. No matter. I reached down, scooped up a handful of fine walnut leaves, and threw them in the air as I ran, pretending there was a stream of debris behind me, just to make me appear I was going a little faster.
People drove by, watching this pathetic runner once more defy all social constraints and defy the normal perception of civilized running, but all I saw was a seven year-old Lorne having immense fun at the age of twenty-two.
I often refer to the runs that I take in the fall as "running into the rainbow," for on those breezy and cool days, leaves blow off trees and into your face and you really do feel as if you're running into a rainbow. That 's how it really feels to me, and I suppose it will have to substitute it for physically jumping into leaf piles lest I be found raking up leaves as part of a community service agreement made by the lawyers of people who REALLY didn't enjoy my presence in their leaves.
Therefore, I will make another all-important step in growing up; not trespassing for childlike fun during my runs. I'll have to have better reasons from now on, I suppose.
Wednesday, August 30, 2006
Banana's have been touched on to define certain emotional outbursts, and have been frozen, dipped in chocolate, and had their peels smoked by a particular type of people in the 1960's. Jokes, certain references and the smell of one left in our book bags for a week have carved the banana into our thoughts forever. Yet, with all of this fantastic press this fruit has gotten through the years, we still forget to just eat them plain and simple.
If you're rushing out of the house in the morning and need something to eat real fast, check out with a banana. If you crave something sweet to pick you up in the afternoon, try letting a banana raise you to new heights. If you have imbibed too much alcohol the night before and wish you hadn't, a banana is your best friend.
On an average, like most fruits and vegetables, the banana contributes 1% of our daily intake of fat, 7% of protein, 10% of calories, 20% niacin, thiamine and iron, 25% magnesium and 35% of vitamin B6. One medium size raw banana contains about 100 calories and about 32 grams of carbohydrates, making it a very useful and healthy energy source. Bananas are soothing to the digestive tract and the large amount of potassium in one banana, about 300 mg., will replace the huge amount lost when we drink too much as well as the potassium deficiencies brought on by certain medications.
Even though just eating a banana plain is pretty good, eating a sliced banana on cereal can be positively blissful. It gets soggy in fruit salad but on a peanut butter sandwich it is the wind beneath the breadth.
Making your own banana bread lets you decide what's in it.
Basic Banana Bread Recipe
Makes one loaf
2 cups of sifted flour
2 teaspoons baking powder
½ teaspoon baking soda
¼ teaspoon salt
¼ cup unsalted butter, softened
½ cup sugar or blackstrap molasses
2 eggs, beaten
3 medium ripe bananas
½ cup milk, yogurt, buttermilk, soymilk, or rice milk
Preheat the oven to 350 degrees. Cream butter and sugar or molasses. In a separate bowl, sift the flour, baking powder, baking soda and salt. Add eggs, bananas, milk, butter mixture and the rest of your ingredients.* When well-blended, pour into a greased loaf pan and bake at 350 degrees for about an hour or until a knife inserted into the middle comes out dry.
*You can add spices to this basic banana bread recipe, such as cinnamon, ground cloves and freshly grated nutmeg. You can add more vitamins in the form of shelled unsalted pumpkin seeds or sunflower seeds, dried apricots, figs dates, cranberries, currents or nuts. In summer, try one with fresh peaches and cinnamon. In fall, try apples. Mash the bananas thoroughly or leave them in small chunks. Make two loaves and freeze one or give one as a gift.
Saturday, August 26, 2006
What you take in: The diet plans to replace two meals and one snack per day with a milk shake. This shake is made from eight ounces of skimmed milk and a powdered drink mix. The third meal should have a calorie count of 600 calories and it should be a low fat combination of nutrient dense foods. The milk shake has a calorie content of 200 calories; hence the total daily intake amounts to 1200 calories.
Positives: The milk shake is made using a formulated mix and hence it is well balanced. So combining it with a meal, makes your meal well-balanced.
Negatives: The pounds return once you go back on solid foods. You also miss on the important plant substances that protect you from diseases.
The grapefruit diet
What you take in: Breakfast consists of half a grapefruit along with a cup of black coffee. Lunch includes half a grapefruit along with an egg, cucumber, a bread slice and plain tea or coffee, while dinner you can have two eggs, half a head of lettuce, a tomato, grapefruit and tea or coffee. The total calories amount to about 800 per day.
Length: Three weeks
Positives: The nutritive content of grapefruit is responsible for all the positive points. Grapefruit is low in calories and sodium but very high in vitamin C. Being rich in water and fibre, it gives you a feeling of being full.
Negatives: Any diet restricted to one food cannot be healthy. The grapefruit diet will not provide you with calcium, a vital bone mineral, iron and many other vitamins and minerals required for the proper functioning of the body.
Food combining diets (Beverly hill diet)
What you take in: You eat a generous serving of only fruits for the first 10 days. Half a pound of bread, two tablespoons of butter and three ears of corn follow this on the 11th day. This continues till day 19th when a complete protein such as steak or lobster is included.
Length: three weeks
Positives: It provides you with a greater variety of foods in the later days and hence can be followed easily.
Negatives: This diet has been judged as extremely low in vital nutrients and may even cause diarrhoea, which further results in loss of nutrients from the body. This diet promotes muscle breakdown to cope with the protein deficiencies.
Cabbage soup diet
What you take in: Drink cabbage soup to your heart's content along with a specific food in unlimited or fixed amounts as specified. On day 1 you can have any fruit except banana to any amount. Day 2 is the vegetables day, which includes a baked potato. On day 3 you can have fruits and vegetables except potato. Day 4 allows you to have a maximum of eight bananas along with skimmed milk. From day 5 onwards you can have non-vegetarian food. On day 6 you can have six tomatoes along with a maximum of 20 ounces of beef, chicken or fish. This is followed by unlimited beef, chicken or fish on day 6. Day 7 is the cereal day and you can have brown rice, vegetables and unsweetened fruit juice.
Length: One week
Positives: You will lose weight quickly while eating as much as you like.
Negatives: Being too low in complex carbohydrates, proteins, vitamins and minerals, this diet results in weakness and a decreased ability to concentrate.
What you take in: You eat all food other than those high in refined sugars. These foods include potatoes, corn, white rice, white bread, beets, carrots and sugar in most forms (moderate amounts of fructose and lactose can be taken). The total calorie intake should amount to 1200 calories per day.
Positives: You decrease your reliance to refined foods, which is the main aim for overall good health. You take in complex carbohydrates as a result of which the fibre intake increases. Fibre has numerous beneficial effects on the body.
Negatives: There is no scientific evidence of fact that increased sugar intake is associated with increase in weight. So you lose weight because of calorie restriction and not solely due to low refined carbohydrates.
Whatever diet you ultimately choose is a call you have to make. But before taking a decision remember to evaluate the pros and cons carefully.
But where they, the school and as parents you go wrong is when this play lessens as they get older. As pressures of tests and exams mount, it's playtime that takes a backseat. However, this should not be the case. Kids should be made aware of the importance of including some amount of physical activity that will continue to run all through their lives. This must be inculcated in them right from the start. The problem starts once the growth spurts settle down, when unspent calories begin to add up and when incorrect habits become a part of the lifestyle. It does not take a "Eureka" to realise that this is one of the gifts you can leave for our children.
Barriers to this utopia
There is a certain mindset that hampers this imbibing. On the one hand, most schools and homes, disregard the child's interest in sports and related activities. Their focus is on pure academics, which they believe will hold them in higher stead. Granted that this is true to some extent, but there has to be a balance inculcated right from the beginning. On the other hand, a misconception most likely made is that brawn and brain do not have their place together. But this is something you can change in our children. Psychologists have recently added sports acumen to be considered as an important component of intelligence.
What can be done
Parents can make up for this lapse by ensuring that play should be a part of their child's everyday life. So be it tennis in the neighborhood, cricket in the building, squash at the sports arena, swimming at the local club or just a game of gulli danda, encourage them to partake of it in good spirit. Parents should also recognise signs of latent talent in their kids and take that extra effort to cultivate and hone those skills. It will add another feather in your child's cap. So if it means driving miles to take them to attend a coaching class, in the long run it may just be worth the while.
Also this should be done in as subtle a manner as possible. Because the minute there is too much pressure from the parent's end without the same enthusiasm from the child, the child loses interest. Parents must also keep in mind that each child is different and should not be compared either with a sibling or friend or cousin, or for that matter, with the child's own previous performance. Neither should their faults be highlighted. The idea is to allow the child to go through the experience itself whatever may be the outcome. The aim of the game is not only in the winning but also in the participation!
Some parents also ask if their child should attend a gymnasium at such a young age. My feeling is that even though there are a lot of kids these days who visit gyms because it's hip, you can find more innovative ideas that will take care of your child's physical activity needs. It is also advisable to allow full physical growth to take its natural course and then start a weight-training program. In the case of very obese children, a simple brisk walk everyday should be able to do the trick, along with sensible diet plans to ensure adequate intake of essential nutrients.
To wrap up, as parents you need to balance play and work in your child's life equally to ensure that your child is not only endowed with brains but also an equal measure of brawn.
Aerobics can counter some of the factors such as obesity, physical inactivity, ageing or even stress, which are instrumental in causing diabetes. In addition, aerobics is also helpful for diabetics because it :
- Lowers your blood sugar levels. This decreases your chances of medical complications.
- Decreases insulin requirements.
- Prevents adult-obesity . Aerobics suppresses the appetite and increases the metabolic rate.
- Enhances your capacity for physical work . This is achieved by developing lean muscle and helps in the control of diabetes.
- Regulates blood lipids and lowers your cholesterol levels.
- Reduces the risk of heart disease through the above benefits.
- Increases your endurance , strength and thus improves your self-esteem.
If you are diabetic and plan to begin an aerobics programme, you must take the following precautions:
- Have the disorder under control . And get your blood sugar tested. It would also be advisable to get your oral glucose test, insulin secretion test and also a stress test done for cardiovascular fitness levels.
- Begin with low-intensity alternative aerobics. Try a few weeks of walking or bicycling to see how your body responds to physical activity.
- Exercise at the same time everyday. This will prevent hypoglycemia if done at the prescribed intensity & duration. Do not exercise when your insulin is at its peak. Have a snack half an hour before exercising.
- Choose the site of insulin injection. Do not inject insulin close to the muscles being exercised since muscle contraction during exercise will push it directly into the bloodstream. This will cause premature hypoglycemia.
- Keep some candies or fruit juices within reach to counteract hypoglycemia.
- Do not perform aerobics more than three to five times in a week. Always take a day off to replenish your body's carbohydrate reserves.
- Stick to low-impact movements. Your insulin requirements will drop as much as 20 per cent during initial adaptation to aerobics. It may take you two weeks to respond to new levels.
- Keep checking the intensity of your workout.
- Ensure a suitable floor surface, shoes, and socks. This is to minimize your chances of injury.
- Take time off during cold and flu season. Diabetics take longer to recuperate so be careful not to contact communicable diseases.
- Know about first aid procedures . And do not leave your class alone, looking for sugar during a hypoglycemic stage.
So in case you are guilty of not exercising because of diabetes, here's your chance to make amends and start exercising in the right spirit.
Friday, August 25, 2006
1. Don't Overeat
Remember that moderation is the key to success. For instance, at parties and weddings, don't go overboard on eating and drinking. As part of your nutritional discipline avoid going to parties on an empty stomach, or else you are bound to overeat. Do you know that 85 per cent of obesity is due to disorders of metabolism? So if you have a tendency to gain weight, then faulty and excessive eating and drinking may only aggravate such factors making it easier for you to gain fat and more and more difficult to lose it later. So eat and drink in moderation, so that you can continue to enjoy eating tasty foods throughout your life. Keep a check on your weight periodically, stick to your nutritional discipline and you will add life to your years. Remember, eat to live not live to eat.
2. Say yes to Exercise
The only way to truly lose weight is to complement your diet with regular exercise. Research has shown that moderate exercise actually depresses the appetite - no wonder that sedentary people tend to eat more than physically active people. This means that inactivity combined with overeating is sure to result in a build-up of body fat. That is why it is important to eat correctly and exercise regularly if you want to lose body fat. You could be walking, running, cycling or doing other aerobic activities which burn calories and reduce fat. The best exercise is that which can be included in your daily schedule and done consistently.
3. Eat Only At the Dining Table
Do you normally eat while watching your favorite soap opera? No wonder you eat more than you actually should be. Good eating habits include eating at the same time each day and only at the dining table. This way you'll be eating only when you are truly hungry.
4. Eat Slowly And Chew Thoroughly
If you have a tendency to overeat, chances are that you gulp your food. Research has shown that when you are really hungry, a fall in blood sugar triggers an appetite mechanism in your brain, creating a desire for food. When you eat, it takes about 20 minutes for your blood to absorb sugar and to circulate it to your brain where the sensation of hunger can be switched off. But if you eat too rapidly, you may overload your stomach before your appetite mechanism has a chance to diminish your desire for food. So the next time you stuff that parantha into your mouth, remember this nugget. Take time to taste and savour each bite. If you eat slowly, chances are you'll experience satisfaction and quit eating when you have had enough.
5. Don't Drink Water with your food
Drinking water along with your meals automatically dilutes the gastric juices which are required in proper concentration to carry out digestion, which is a must for good health and maintenance of ideal weight.
6. Avoid Junk Food
Next time you want to have a cola, reach for that glass of freshly-squeezed juice. Difficult as it may appear to be, limit your intake of junk food, as it is high in fat. Do you tend to stuff yourself with refined foods, snacks, cakes, pastries and desserts? Unfortunately, all that they do is add up to your fat deposits, without giving you balanced nutrition. If you have a sweet tooth and find it difficult to resist sweets, keep a ready supply of fresh fruit salad, puffed rice, popcorn, curd, skimmed milk etc. to satisfy an irresistible urge to snack. Limit your intake of sweets, chocolates, ice-creams, pastries to only a few bites and that too preferably after you've eaten your balanced meal.
7. Remind Yourself Of Obesity & Health Hazards
Never forget that being obese is an open invitation to heart disease, high blood pressure, diseases of the gall-bladder, diabetes, joint pains, various forms of hernias, cancer etc. So keep working towards maintaining your ideal weight. With a slim & trim figure and a new you, bring happiness back into your personal and professional life. Stick to your regimen of daily exercise and a balanced diet and you will improve
Monday, August 21, 2006
1. Atkins Diet
By eating foods high in protein and fat and limiting foods high in carbohydrate, we can increase our metabolism. Atkins proposes that eating a large amount of carbos results in overproduction of insulin, which leads to increased hunger pangs and consequently weight gain. Thus consuming protein and fat is highly encouraged, while carbohydrate intake is limited to between 15-60 grams per day.
Many people like feasting on foods rich in fat such as steak, bacon and butter, especially since these foods aren't typically considered diet foods. For others, the increase in protein decreases food cravings and leads to rapid weight loss.
The flip side is that eating unlimited amounts of saturated fat can lead to an increased risk of heart disease. A diet that limits carbohydrates causes the body to rely on muscle or fat for energy (recall that carbohydrate is the body's primary fuel source). When the body breaks down stored fat to supply energy, ketone is formed. Ketones may suppress appetite, but they also cause fatigue, nausea and a potentially dangerous fluid loss. Anyone with diabetes or heart or kidney problems should not follow a diet that promotes the formation of ketones. The overwhelming consensus is that this diet is a complete failure. Any weight loss is immediately regained (and usually more). It's unhealthy and dangerous!
2. Blood-type diet
Depending on your blood type, there is a detailed list of foods to avoid. This is because each blood type has its own antigen marker that doesn't react well to certain foods.
Do you like the idea of eating only certain foods? Do you enjoy measuring foods and timing every meal? If you answered yes to both, then this diet may be for you.
But the odds are that if your blood type is 0 positive and your spouse is AB negative, then you've got your work cut out for you with regard to food shopping and cooking. The list of each blood type's food restrictions eliminates specific groups of foods -- that means you're guaranteed to miss out on nutrients you need. Most experts expressed amazement that a diet premise this absurd found a following. What's blood type got to do with weight loss? According to the experts, nothing.
3. Juice Fasts
For one to five days, you drink juice and nothing but juice (100 per cent fruit and vegetable juices). You may dilute your juices with water, but no salt, sugar or additives are allowed.
The good thing is that you don't have to think about what you'll be having for breakfast, lunch or dinner, because it'll always be the same: juice. The pounds will appear to drop off because of the very low calorie intake (although you're really losing mostly water). Some believe juice fasts allow the body to rejuvenate and cleanse itself.
But if you are living only on juice, then you’ll soon turn into a couch potato, having energy only to flip channels. This diet will also slow your metabolism to a grinding halt in the fastest possible time. And what about returning to solid foods post-fast? Ease back in with foods that are easy to digest because your tummy has taken a vacation and needs some time to get back up to speed.
You're asking for trouble when you try fasting (unless you're supervised by a physician). Your body is usually worse off after the fast than when you started. This happens because your body will try to protect itself for the next time it is starved by storing excess calories as soon as you stop fasting. This means you could eat less than you ate before the fast and yet gain weight.
4. Low-fat diets
Fat has more than double the calories of carbohydrates and proteins, so if you reduce the fat in your diet you'll lose weight. Only 20 per cent of the calories you eat come from fat, so the foods at the very top of the food pyramid (butter, mayonaisse, salad dressing) are greatly reduced or eliminated. Swap fatty foods (fried, snack foods, cheeses, meats) with lower-fat versions or eat smaller portions. If you are at risk for heart disease, obesity or cancer, then reducing your intake of saturated fat (animal fat, cheese and dairy products) is a smart choice. Low-fat diets promote foods like fruits and vegetables, which are low in fat and rich in nutrients.
A low-fat diet isn't healthy and won't work if those low-fat or nonfat foods are not fresh. Eating foods high in sugar, but low in fat inevitably leads to the snackwell syndrome. This happens when a large quantity of fat-free snacks are consumed because they don't contain fat. Often, fat-free is confused with calorie-free, so you think it's okay to polish off the box. Fat-free processed foods will definitely cause you to pile on the pounds if you eat too much.
Eating excess fat is not the only reason people gain weight. You gain weight when you eat more calories than your body can use. Studies show that people who cut down fat intake well below 30 per cent tend to add more calories to their diet because they're hungry. The less fat you have in your diet, the hungrier you'll be. The American Dietetic Association recommends that less than 30 per cent of the day's total calories should come from fat and less than 10 per cent from saturated fat.
5. The Pritikin diet
Developed to treat heart disease, Pritkin is a very low-fat, primarily vegetarian diet that is based on whole grains, fruits and vegetables. Which foods aren't allowed? Processed foods such as pasta and white bread, animal proteins, eggs and most types of fats.
Who would dispute the health benefits of eating more fruits, vegetables, whole grains and less fat? This diet is perfect for those who don't like calorie counting or watching portions. However, low-fat diets often increase hunger leading to overeating. When you significantly decrease the fat in your diet, your body will start craving calories from sugars and carbohydrates. Pritkin can also be low in vitamins and minerals, due to the elimination of many types of foods.If you have heart disease or a strong family history of heart disease, then Pritikin is the answer for you. When it comes to weight loss, this diet is too low in fat and restrictive to stay on long enough to lose weight and keep it off.
6. The Zone diet
Like the Atkins diet, this is a high-protein diet. It proposes that a higher protein, lower carbohydrate diet decreases hunger and consequently weight. Unlike Atkins, the Zone allows greater carbohydrate intake: the diet's breakdown is 40 per cent protein, 30 per cent fat and 30 per cent carbohydrate. All meals and snacks follow this 40:30:30 ratio, which allows the body to work within its peak performance zone for utmost energy and weight loss.
The Zone's low-calorie intake allows you to drop weight rapidly while eating foods like bacon and steak. The health risks, like heart disease and cancer, are similar to the Atkins Diets, though little lesser as Zone allows for more healthy carbohydrates, such as veggies and fruits. You may drop pounds quickly, but you regain them just as fast once you go off the diet. Lastly, the time it takes to follow the Zone's stringent guidelines is like having a part-time job.
The Zone's popularity can be attributed to good word of mouth because people have lost weight on the diet. Why does it work? Because it's a low-calorie diet in disguise. When you decrease your calories, weight loss will soon follow. But as soon as you eat that extra bite, you know what your body will do with it. Both the American Dietetic Association and the American Heart Association disapprove strongly of the Zone primarily due to its high protein content.
Now that you know more about the different kinds of diets, it might make it easier for you to decide which diet you want to follow. On the other hand, it might just make it all the more harder.
Thursday, August 10, 2006
Your metabolism is what tells your body how many calories it needs to consume to keep it going. Our metabolisms can get stuck at some point and sometimes need a kick-start to get going again. The best way to speed up a stuck metabolism is by building up your muscles. To build muscles, men and women should begin lifting weights or strength training.
How does lifting weights speed up your metabolism? By building muscles. A pound of muscle burns 20 times more calories than a pound of fat. Even while you are sleeping, reading a book, surfing the Internet or doing aerobics, stronger muscles are burning more calories than weak muscles or fatty tissue. Muscles need more caloric energy to keep them working. Your dieting and all other physical exercise will be more effective if you have strong muscles. You will find you will lose and keep off the weight better too.
Our bodies can lose muscle mass at anytime during our life. But most people start losing muscle more rapidly at around age 40. We can lose a half a pound a year of muscle if we allow ourselves to. Around this age, or at an even younger age, many women and men start seeing their weight going up, up and up. It is true that the metabolism changes and slows down around age 30 or 40, but this is directly related to muscle loss and can be counteracted with strength training.
The best way to keep your metabolism high is to lift weights and build those muscles back up. It is never too late to start. The muscles you build from lifting weights are more compact and will look better in your clothes too. Another added benefit of weight training is a reduced risk of osteoporosis. You do not need to go to the gym to lift weights. You can buy three-pound, five-pound and eight-pound weights to begin with, and work out at home.
While you are building up your muscles to burn more calories you can continue to diet. By understanding how many calories a healthy strong muscle can burn in a day your diet will be more effective. Here is what you need to know about dieting, burning calories and exercise:
To lose one pound of stored fat you must decrease your calories; either by decreasing your caloric intake of food by 3,500 or burning 3,500 calories through exercise or a combination of both. You cannot, and should not, do this all in one day; but over one week would be reasonable. A woman who normally consumes 2,500 calories a day, can reduce her caloric intake by 250 a day, then lift weights and do an aerobic activity to burn another 250 calories or more. This will equal 500 less calories per day. She would lose one pound a week and four pounds a month with this routine. Double the exercise and decrease the food intake further, and she will lose two pounds a week. That is eight pounds a month. This is a good combination of diet and exercise. It is important to remember, however, to avoid serious medical risks, nobody should consume less than 1,500 calories a day.
Make your dieting more effective; begin burning more calories 24 hours a day with your new stronger muscles, even while you are sleeping. Remember a pound of muscle burns 20 times more calories than a pound of fat. Turn that fat into muscle and you will love the results. Start slow and continue strength training today. You can join a gym to learn how to lift weights or buy a video and lift small weights at home. However you do it -- make sure you do it! The results will be amazing.
Sunday, August 6, 2006
The University of Connecticut Health Center did a 10-year study with adults at least 60 years of age. They worked up a program to bring the participants into the best possible shape and increase their strength, and endurance.
If you want to put a halt to the inevitable decline in physical strength, then this program is for you. This is a good exercise program that reduces the physical effects of aging and in many incidences actually increases physical power.
The key is to do both cardiovascular and weight-bearing exercises. You can join a gym, health club or exercise class at a senior center, or you can work out on your own. The main thing is to combine the two physical exercises. Even ordinary things such as gardening and cleaning your house can help, but it isn't enough. You need a concentrated exercise routine. Experts recommend three times a week for one-hour sessions. You alternate between cardiovascular workouts and weight training. In between the sessions you should walk.
An exercise program is important not for a short period of time but for your life. The hope is that you will continue and stall some of the effects of aging. The ideal is to work on difference sections of the body and devote about 15-minutes to each part. So that is 15-minutes to concentrate on the lower body, upper body, abdomen and back. A wonderful side effect is increased balance. This is very important because many injuries such as hip fractures are due to poor balance.
According to the University of Connecticut study the resistance exercises and weight training improves strength and balance even in frail elderly. If you want to remain independent as you age into your 70s and 80s, start your exercise program today.
Recent research has found that when it comes to exercise, you need a combination of three types: weight training for strength; aerobic exercise for strength and endurance; and calisthenics (stretching, bending and twisting exercises) for flexibility. Studies have found that violent physical exertion is no more useful to gaining and maintaining fitness than is moderate exercise. What is more, violent physical exertion can result in an increased risk of injury or heart attack for those who are not in prime physical condition. So, start off slow and go slow with your new exercise program.
Walking and other aerobic exercises done at a pace that makes you breathe a little harder and work up a mild sweat for a half hour to one hour, three days a week, will keep your heart, lungs and vascular system in good working order while strengthening your bones and muscles.
Exercise intensity for aerobic conditioning is measured by heart rate. A good activity level is 70 percent of your maximum heart rate, which is determined by subtracting your age from 220. Thus the recommended exercise heart rate for a 60-year-old person is 112 beats per minute. People who have not been exercising should begin using 60 percent of their maximum heartbeat as the target heart rate and can ultimately move up to 80 percent once they have reached their maximum fitness level.
Do not attempt a strenuous workout during hot, humid weather, and wait until at least two hours after eating before engaging in moderate to heavy exercise. Warning signs of overexertion include an inability to talk, dizziness or disorientation, nausea, or pains in your chest, upper back, left shoulder or arm. If you have any of these symptoms, check with your physician as soon as possible.
To avoid excess strain on the heart and injury to your muscles, warm up for about five minutes before working out, and cool down after exercising. Never abruptly stop exercising, since the sudden stop in motion can cause lightheadness or muscle cramping.
Walking is a good exercise because it can be done at a pace that you easily can set for yourself, it takes no equipment other than a pair of good walking shoes, it can be done at virtually any time, and it can be done on your own. Walking strengthens muscles in the lower body, helps to repair joints, bone and tissue, and helps to ward off or slow osteoporosis. Since walking only works the lower half of the body, other aerobic exercises as well as exercises that increase flexibility should be included in your routine. Other good aerobic exercises for weight-bearing joints include dancing, tennis, racquetball, basketball and biking.
Before beginning an exercise program, check with your personal physician and start off slow to avoid overexertion and accidents. Stick with it. Varying the type of physical activity you engage in will help to use all the major muscle groups in your body and avoid overuse of any one major muscle group. It will also prevent boredom.
Aerobic exercise not only strengthens your bones and muscles, which helps to prevent osteoporosis, it also strengthens your heart and helps to maintain your lung capacity. Aerobic exercise slows or prevents the buildup of cholesterol plaque in the veins and arteries (atherosclerosis), and helps to ward off arteriosclerosis, or hardening of the arteries, by keeping them flexible, thus reducing high blood pressure, which plays a major role in heart disease and strokes. Exercise also improves the functioning of the liver, pancreas and other vital organs.
Sustained aerobic exercise can help to control late onset or type II diabetes mellitus since it aids in the metabolism of sucrose (before beginning an exercise program however, one with diabetes mellitus should undergo a detailed medical evaluation with appropriate diagnostic studies). What is more, exercise helps to spur the production of human growth hormone, which otherwise ceases to be produced after about age 50. Human growth hormone helps to maintain the size and strength of muscles that diminish as we age.
If you have arthritis and other joint or motion-impeding conditions, swimming is an excellent aerobic exercise. It offers many of the benefits of other aerobic exercises without putting undue stress on joints that, because of arthritis or injury, are unable to repair and rebuild themselves in the normal manner. Swimming, however, unlike weight-bearing aerobic exercises, does not aid in the rebuilding of bone; therefore, it is not helpful in preventing or slowing osteoporosis, nor does it appear to be helpful in reducing weight.
Physical exercise not only increases the metabolic rate so that more calories are burned during the activity, it also continues for several hours after you have stopped. What is more, as you improve your muscle tone and enlarge your muscles, they will burn more calories even when you are engaged in sedentary activities.
Perhaps all of this isn't news to some, but if it is, keep in mind the old adage, 'An ounce of prevention is worth a pound of cure.' Whether you're 19 or 90, it's never too late to get into shape.
Nutrition information is proliferating in cyberspace. Your computer can take you to breaking nutrition news, the latest weight loss advice, nearly endless nutrition resources, interactive online diet programs and even the chance to 'chat' with professionals. However, you still need to separate fact from fiction.
Like other media, the "information super highway" is also littered with biased opinions, questionable advice, and sometimes flat-out misinformation. Use the same healthy skepticism with online information that you use to evaluate other nutrition information in the "brick" and "mortar" world.
How can you determine if a Website provides sound nutrition information?
Be your own nutrition "myth" information detective. Use this checklist as your guide.
Does the site:
- Identify its owner or sponsor? That's a clue to the site's perspective or potential bias.
- Name its content contributors, along with their credentials and an affiliation, if applicable? For instance, does the site have nutrition content writers who are true nutrition experts, such as registered dietitians?
- Base its facts and figures on cited, science-based sources, not just opinions? Opinions can be intriguing and informative, but only when you know they're opinions and they're not disguised as solid facts.
- Provide links to other credible online sites? Check out the links yourself.
- Have regular updates and postings? If so, it's usually a better (but not fool proof) indicator of sound nutrition information than one with irregular updates or only periodic postings.
- Seem to have a bias, as in, does it sells products based on the site's nutrition information? Judge for yourself, see if you believe there's a connection.
Happy nutrition myth-detecting!
Saturday, August 5, 2006
- Stretch slowly and in a controlled motion
- Don't bounce
- If you experience pain let up on the stretch or stop
- Don't compare your flexibility with someone else's
- Breathe slowly and rhythmically
Don't hold your breath
Stretching slowly will allow your muscle to lengthen itself more slowly. This will relax the muscle more and reduce the risk of quick movements ripping the muscle in an unpleasant way. If the motion of the stretch is controlled, as opposed to quick and jerky, the muscle is ensured to get a full stretch.
Bouncing to try to ease the pain of the stretch will not increase flexibility. Bouncing is an inconsistent movement in a stretch that will increase the chance of injury and decrease getting a good stretch.
Going with the theme of injury, stretching can be as painful as a weightlifting injury. If you feel pain while stretching, you are stretching too far. It doesn't matter how far you stretch really. It only matters that you are stretching. Stretch as far as you feel you can without pain. After a good workout the last thing you want to do is pull a muscle stretching.
All people are at different levels of flexibility. Don't worry if you are not Richard Simmons. Very few people will be able to stretch like Plasticman at first. (Note: if you ever stretch like Plasticman, start a movie career or tour with the circus).
Breathing slowly and in a rhythm helps you and your muscles to relax. Breathing rhythmically will usually come naturally if you are relaxed.
Holding your breath can be a sign that you are stretching to far. If you are stretching too far and it becomes painful, the tendency is for a person to hold their breath. It is a good idea to keep a steady breathing pattern anyway, as the human body often responds well to consistent patterns and rhythms. It can help you relax, which is of course they key to stretching well.
Vitamin K is known as a fat-soluble vitamin, which means that it dissolves in fat. Fat is what carries this vitamin throughout the body and aids in its absorption. Fat-soluble vitamins can be stored in the body, so it is important to get only needed amounts.
There are several different forms of vitamin K. Phylloquinone is the natural form of vitamin K. Menadione is the synthetic form of vitamin K. Menaquinone is the form that is produced by the body. Vitamin K is made in the body, as well as obtained from the diet.
The primary function of vitamin K is to help make a protein called prothrombin, which is essential for helping the blood to clot when you are bleeding. It also helps the body make some other body proteins for blood, bones and kidneys.
Foods it is found in
The best sources of vitamin K include green leafy vegetables, such as spinach, broccoli and turnip greens. Several other foods provide smaller amounts such as milk, other dairy products, meat, eggs, wheat bran, wheat germ, cereal, some fruits and other vegetables.
The body is also able to produce vitamin K from certain bacteria in the intestines.
How much you need
The RDA (Recommended Daily Allowance) of vitamin K for females age 11 to 14 years is 45 micrograms; age 15 to 18 years is 55 micrograms; age 19 to 24 is 60 micrograms; and for females 25 and over the RDA is 65 micrograms. The RDA of vitamin K for males age 11 to 14 years is 45 micrograms; age 15 to 18 years is 65 micrograms; age 19 to 24 is 70 micrograms and for males 25 and over the RDA is 80 micrograms.
Not getting enough vitamin K can cause blood to not coagulate or clot normally. Vitamin K deficiency is very uncommon except for in the cases of rare health problems. Chronic use of antibiotics can destroy some of the bacteria in the intestines that produce vitamin K, which can cause a problem.
No symptoms have been observed when consuming too much vitamin K. Moderation is always the best policy. The most toxic form is supplements. Because of this, vitamin K supplements are usually only available through prescription. People that take blood-thinning medications or anticoagulants need to eat foods containing vitamin K in moderation. If you take these types of medications make sure to ask your doctor about vitamin K.
Sunday, July 30, 2006
The popularity in stationary spinning bicycle classes has taken the health clubs by storm. Fitness enthusiasts are always looking for new and fun ways to get a great work out with a little spunk. Workout classes featuring cardio machines, blaring music, and of course, funky names are spreading like wildfire!
While you're likely to work up a sweat and feel the burn no matter which you take, not all are created equal. Here are some new classes to look out for in your health clubs.
- Spinning: With a souped-up exercise bike, cyclists get in gear with a mix of slow-and high-paced intervals. Even if you've never been a big fan of stationary bikes, this class is something completely out of the norm. It is a great motivator and gives you a fantastic workout. Beginners shouldn't expect themselves to complete the class the first go around. It is a tough one and you should work your way up to it. Even the fittest bodies out there will be challenged and fatigued!
- Trekking: On a treadmill you run, walk or sidestep up a grade or on level ground. This is a great workout for anyone. You have more control of your speed, grade and overall routine vs. the spin class. Be sure to bring a towel and see just how creative we've gotten with the treadmill. You'll also take with you some new tricks that you can use to spice up your solo treading!
- Precor Fit: Using an elliptical trainer ,you pedal in an oval motion while your arms get a workout, too! This class is a little on the trendy side. The lasting power of this class is questionable. It might be harder to find this class in the smaller gyms. It is primarily being tested in large markets in big cities.
- Boathouse: Ouch! This class is done with a rowing machine (you know those machines you hardly ever see anyone on because they are so much work). This class mixes up the effort and the emphasis on your arms, legs and back. No doubt about it … this class gives you the best full-body workout. However, the variety the class offers is pretty limited. This is not for beginners; it is for the exercise maniacs!
- Stomp: On a stair climber, get in step one leg at a time or jump on the pedals with both feet. Stomp this class right off your list. I hate stairs to begin with and even with all the great energizing music I still felt I was climbing the stairway to hell! From the looks on the other participants' faces, I wasn't alone!