Thin stay thin while fat get fatter

The average weight among people who are overweight or obese has increased dramatically in the last 10 years.

But among those who are thin there has been little change - Cancer Research UK scientists announce today.

Almost 12,000 men and women had their weight and waist measurements taken in 1993/4. Researchers then compared these statistics with weight and waist measurements in a similar sample taken from the Health Survey for England 10 years later.

People who are overweight or obese have an increased risk of cancer. Male obesity had risen from 13.4 per cent in 1993/4 to 22.7 per cent in 2003/4 and female obesity from 15.8 per cent to 22.4 per cent according to the study published online today in the International Journal of Obesity.

Men's waist circumference increased by 3.48 cm and women's increased by 4.35cm.

Researchers also found that the proportion of men and women under 45 who were morbidly obese (with a BMI of over 35) doubled over the 10 year period - as did the proportion of women with a BMI of more than 40.

Professor Jane Wardle, director of Cancer Research UK's health behaviour unit and study leader, said: "We found that weight gain in the population has been unequally distributed. Slimmer adults today are almost as slim as their counterparts 10 years ago but the heaviest people in the population are much heavier than they were 10 years ago.

"These inequalities are greatest among those under 45, suggesting that environmental changes are having a greater impact on young adults. Snacking habits, takeaway meals high in fat and sedentary lifestyles where many people spend both work and leisure time sitting in front of a computer are all likely to contribute to the results.

"It seems that some people are more susceptible to changes in the environment than others and the explanation for this may be partly genetic. It is important for psychologists, geneticists and biologists to work together to discover the reasons for this."

Dr Lesley Walker, director of cancer information at Cancer Research UK, said: "This research adds to the evidence that the UK is in the grip of an obesity epidemic. We know that high body weight increases the risk of a number of cancers and it is important we get this message out to as many people as possible.

"A healthy diet with plenty of fibre, fruit and vegetables as well as regular exercise can help people to lose weight and reduce their risk of cancer. Cancer Research UK, together with the charity Weight Concern, has devised Ten Top Tips to help people control their weight."

http://www.cancerresearchuk.org/