Q & A: Can you be too thin for good health as well as too fat?

Are all healthy diets slimming?

No. There is more potential to lose weight on a healthy diet, mainly because it is harder to eat too many calories on a diet that contains the recommended amounts of fruits, vegetables, salads, complex carbohydrates, lean protein, and so on. A healthy diet is high in 'bulk' but fairly low on density (calories per gram weight).
But it you don't pay some atttention to portion size, or if, say, you snack on hefty amounts of healthy nuts, seeds, or bread between meals, you could easily exceed your required number of calories and end up putting on weight.

The only way to lose weight is to create an energy deficit in your body by burning up more calories than you take in. There is some small advantage to be gained by the type of food that you eat (e.g. protein and carbohydrate will tend to store fewer calories on you than fat does) but in the total scheme of things, the difference won't be huge.

I hope I haven't put you off following a healthy diet while you slim - there are many other advantages to eating a perceived healthy diet - as an example, you are less likely to suffer from hunger pangs. And of course, you will be doing your body more good by slimming on a healthy diet than on a ridiculous one.


How do I keep 'regular' while I'm slimming?

Some diets do predispose to constipation but you should be able to avoid the problem if you obey the following guidelines:

Don't diet on too few calories. If you don't eat enough, your system won't process your food properly. Aim to diet on no fewer than 1250 - 1500 calories for women; 1500 - 1750 for men.

Don't follow a high-protein, low-carbohydrate diet. A low carbohydrate diet will also be a low-fibre diet, and inadequate fibre is strongly linked with constipation.
Instead choose a high-carbohydrate, moderate fat diet and make sure that most of the carbohydrates that you eat are whole (e.g. fruits, vegetables, roots, pulses, brown rice, wholewheat pasta, wholegrain bread) rather than refined (e.g white bread, white rice) because refined carbohydrates have had a great deal of their fibre removed.

Eat at least your 'five' portions of fruit and vegetables a day, and drink plenty of water. For fibre to work properly you need adequate fluid. Fruits and vegetables are very high in water (e.g. an apple is 84% water, cabbage is 90% water). Six glasses of water a day should work well.

If these measures alone aren't enough, also try adding more foods that seem to have a particularly good laxative action to your diet. These include citrus fruits, rhubarb, spices, cabbage, prunes, figs, and garlic, although people do vary in their own reactions to these. Don't start using strong laxative pills as you can get dependent upon them so that when you stop using them you are more constipated than ever.

Lastly, take half an hour or more of vigorous exercise a day - this seems to boost all the body's systems, including digestion and elimination. Stomach exercises, too, can help.


Can you be too thin for good health as well as too fat?

Yes. The recommended healthy weight falls between a Body Mass Index of 18.5 and 25. If your BMI is lower than this, you are considered to have an unhealthily low weight which may predispose you to health problems including cessaton of menstruation, conception problems, osteoporosis.
Some experts believe that a BMI lower than 20 is actually too thin, and as you get older it may be best to consider a BMI of around 22 - 23 as a good lower level to aim for. Also, maintaining a low BMI (say, 20 - 22 or 3) may not be a good idea later in life for women, as fat has been described as 'nature's HRT' - it helps to maintain oestrogen levels in the body.

If you check out your BMI and find you are too thin, see your doctor for advice both on whether your thinness may be a symptom of a medical condition, or for nutritional help. If you feel you may have an eating disorder which is making you thin, visit www.edauk.com - the website of the Eating Disorders Association.


What causes an apple shape, why is it unhealthy and how can I beat it?

The apple shape (surplus weight stored mainly around the abdomen and waist - also called intra-abdominal fat or central fat distribution) is linked with health problems such as coronary heart disease and diabetes, whereas the pear shape (heavy hips, bottom and thighs) does not appear to present the same level of risk.


This shape is predominantly a male phenomenon although women are more prone to develop an apple shape in mid life, particularly after the menopause. This is because the female hormones are present in much smaller amounts and so the shape tends to become more 'male'. There is also evidence that abdominal fat develops when you are under long term stress and tension. The hormone cortisol is released during stress, and it seems that high levels of cortisol in the body tend to encourage central fat to accumulate. Researchers at Yale University studied 60 women and found that the more stress they were under, the more fat they stored around their stomachs.

In other words, the people most likely to develop an apple shape are stressed men of any age, and older, stressed women.

The apple effect can be minimised with a sensible diet, regular exercise and stress reduction techniques (in fact, exercise is a good stress-buster anyway).

You can tell if your pot really is too big for your own health by doing the Waist Circumference Test. Simply measure your waist at its smallest point and check out here:

MEN: Waist over 37 inches indicates slight health risk; take care.
Waist over 40 inches indicates substantially increased health risk.
WOMEN: Waist over 31.5 inches indicates slight health risk.
Waist over 34.5 inches indicates substantially increased risk.

The Waist to Hip Ratio
Another way of assessing whether or not you are a healthy shape is to discover your Waist to Hip Ratio. This is simple to do - just divide your waist measurement by your hip measurement, using a calculator. The result is your WHR (waist to hip ratio). For men, a figure over 0.95 and for women, a figure over 0.80 indicates excessive intra-abdominal fat and increased risk to health.


How often do I have to exercise to lose weight?

To lose a pound of fat you need to burn off about 3,500 calories in excess of your normal weight mainenance needs. So to lose a pound of fat via, say, brisk walking, you would need to do about ten hours of walking.

I always say that if you can lose half a pound of bodyfat a week through exercise, you are doing well. That would translate into seven 40-minute walking sessions at 240 calories each. This roughly equates to the recommendation from the American College of Sports Medicine that 30 minutes or more of moderate intensity exercise such as walking, is done on most, or preferably all, days of the week.

But how often you need to exercise to lose weight depends upon how much weight you have in mind to lose via exercise, what type of exercise you choose, and how long your session lasts.

For maximum weight loss, one would have to do regular daily exercise of high aerobic intensity (e.g. running, fast cycling, crawl swimming) for long periods of time, and add resistance (weight) training into your schedule too as muscle is ore metabolically active than other body tissue. But if you are unfit, you need to begin any exercise programme gently and build up fitness gradually, so such a hard regime would be neither wise nor possible.

Even in the long term, though, most of us aren't that keen, or haven't that amount of time to spare to carry out an extreme regime, and will be happy with slow bodyfat reduction thanks to a sensible, more attainable exercise programme and a moderate calorie-reduction diet.

A research paper published in the International Journal of Obesity in 2001 concluded that 'a substantial but manageable amount of exercise is required for weight control' equating to about four hours' walking a week.

And two recent studies have found that in the battle against surplus weight, it is regular moderate exercise that achieves better results than intensive bursts of exercise. One of the studies, from Maastricht University in Holland, found that people who do a weekly intense session at the gym end up expending less energy over the course of a week than people who regularly do moderate exercise such as walking or cycling. Adding extra activity into your daily life in the form of non-formal exercise such as running up stairs will also help create an energy deficit.