Thursday, July 24, 2008

Chitosan - An Aid for Weightloss

Chitosan has been shown to be an effective supplement in the ongoing fight of Americans against obesity. Research is continuing and knowledge is growing. When used in a sound dietary and exercise program, chitosan can become another weapon in the arsenal.

What is Chitosan?

Chitosan is a fiber made from chitin, the second most common fiber found in the natural world, after cellulose (the plant fiber found in celery, bran, broccoli, etc.). Chitosan is made from crab, shrimp and lobster shells, but the most effective (and, unfortunately, most expensive) type of chitosan is made only from the shells of shrimp.

Chitosan was introduced in the natural foods industry in the 1990's as an aid to weight loss. There is also some evidence that chitosan can lower blood cholesterol and blood pressure. Some researchers have even suggested that chitosan may have a beneficial effect on joint disease and osteoporosis. At the present time, it is unclear how these effects are produced. Clinical trials are being conducted on human beings in order to more fully understand the mechanism of action. Chitosan has been taken by human beings for decades and has shown no significant side effects.

Chitosan, Fats, Digestion and Weightloss

Fats are an essential part of the human diet. Fats are a component of the cell membrane in every cell in the human body. Fats also provide the building blocks for hormones and support the immune response. Unfortunately, fats contain more calories per unit volume than any other food source; more than simple carbohydrates like sugar and more than protein. Dietary fats (also called triglycerides) must be chemically modified before they can be absorbed into the blood stream and either used for energy, stored in fat cells or deposited in streaks along your arteries. The digestion of fat occurs mainly in the small intestine. The human body is very good at absorbing fat because it is such an extremely rich source of calories. If you had to run across the plains all day to catch your food, or walk forty miles a day to gather enough berries and roots to feed yourself, you would eat as much fat as you could find. Most of the fat ingested through our diet is absorbed; less than 5% of dietary fat remains unabsorbed.

Bile salts, which are a made from blood cholesterol in the liver, act as emulsifying agents - a sort of "detergent" to help disperse drops of fat in the diet. Digestion and absorption is then accomplished with the help of enzymes that are also produced by the liver. These enzymes break apart the chemical bonds that hold the triglycerides together. The body then separates the bile salts from the fat particles before the fat is absorbed into the walls of the intestine and into the blood stream. The bile salts are then reabsorbed and returned to the liver for recycling to do their job all over again. Over 24 hours, from 11 to 40 grams of bile salts and enzymes may be secreted into the small intestine and recycled again and again.

It is clear from research in labs, on animals, and in humans, that chitosan binds both bile salts and fats in the intestine and causes them to be excreted without being absorbed or reabsorbed. This means that the liver must now produce new bile salts and enzymes to be sent into the intestine. To do this, the liver must draw more cholesterol out of the blood to create new bile salts and enzymes. Some recent research has proposed a more complex view of the mechanism of action, but the outcome is clear, blood cholesterol is lowered and fat (along with its heavy dose of calories) is excreted. Studies have been carried out on rabbits, rats, mice, chickens and people. The effect of chitosan on animals is similar to the effects on people, but the manner in which this takes place may be different. Research in this area is ongoing.

Studies on human beings have shown that chitosan is a more effective fiber than plant fibers such as cellulose or pectin. In fact, in animals, chitosan has even been found to have an appetite suppressing effect, causing the animals to actually eat less food. In a study of human beings eating their normal diet, however, there was no weight reduction and no cholesterol reduction, suggesting that chitosan alone cannot provide the "magic bullet" to weight reduction, but may play a significant part when combined with a diet and exercise regimen.

Points to Remember When Adding Chitosan to Your Diet

  • Chitosan is a highly concentrated substance. One of the things that makes chitosan so effective is that it expands in the stomach and in the intestine. This means that you must drink at least one eight-ounce glass of water along with the chitosan capsules so that the chitosan can begin to "fluff up" and be ready to bind to the fat and bile salts. Secondly, the chitosan should be taken twenty to thirty minutes before lunch and again before supper. This gives the chitosan time to expand and may help with appetite suppression, as well.

  • Chitosan absorbs all fats. That means that the important oil-based vitamins (such as A, D, and E) that you also take every day will also be absorbed. It is not recommended that you take chitosan before all three meals in the day. Remember that chitosan works along with your diet and exercise program to help reduce fat absorption and lower cholesterol. Therefore, take your fat-soluble vitamins with a low-fat breakfast and take chitosan before lunch and dinner. That way, the chitosan will not cause a deficiency of these important vitamins.

  • You should become familiar with the labels ingredients lists of weight loss products that claim to use chitosan. There are some products on the market today that contain very small amounts of chitosan. These products make extravagant claims for weight loss and include other compounds not proven to have such effects. Furthermore, some chitosan products are made from the shells of a mixture of lobster, crab, and shrimp. The molecular weights of these forms of chitin vary. The most effective chitosan is made only from the shells of shrimp. In fact, one form of chitosan is patented under the name of "Absorbitol" and contains only chitosan made from the shells of shrimp. Absorbitol has been tested repeatedly to have significantly higher levels of fat absorption than other types of chitosan. Several reputable companies market this patented chitosan.

  • The effects of chitosan vary according to dose. Most brands of chitosan come in 250 mg or 450 mg clear capsules. The bottles recommend that you take four of the 250 mg capsules before lunch and again before dinner, or two of the 450 mg capsules. Taking more chitosan than this does not increase the effectiveness and may lead to constipation, so do not exceed this dose.

Chitosan is only effective when combined with a healthy diet and exercise program. Do not underestimate the power of a low-fat diet. Diet and exercise combined is the only proven way to weight loss. Either one alone is not effective. When you diet without exercise, your body thinks you are experiencing a famine and immediately begins to make more efficient use of the calories that you are still consuming. If you continue to diet without exercise, your body gets so efficient at using calories that you can gain weight on a granola bar and a can of green beans. However, if you add exercise, your body knows you are in a famine situation AND under physical stress at the same time and it mobilizes all of its fat reserves to ensure survival. This is when the weight comes off.

No comments: