Atkins? The Zone? The Grapefruit Diet?

How do you choose a diet?

Well, one of the longest and largest studies to compare weight-loss techniques has found that a low-carb diet and a Mediterranean-style regimen helped people lose more weight than a traditional low-fat diet.

    An even bigger surprise was that the low-carb diet improved cholesterol more than the other two.    Some critics had predicted the opposite.

    However, all three approaches _ the low-carb diet, a low-fat diet and a so-called Mediterranean diet _ achieved weight loss and improved cholesterol.

    The study is remarkable not only because it lasted two years, much longer than most, but also because of the huge proportion of people who stuck with the diets _ 85 per cent.