Buxom bum healthier than tubby tum
Researchers who persuaded volunteers to gorge themselves on ice cream and sweets to gain weight have discovered why a big belly may be a greater health risk than thick thighs.
Previous studies have shown that abdominal fat heightens the risk of heart disease, strokes and diabetes, while fat expansion in the lower body around the thighs and bottom seems to reduce the risk.
Dr Michael Jensen, of the Mayo Clinic, in Rochester, Minnesota, and colleagues overfed 15 men and 13 women over an eight week period using ice cream shakes, sweets and high-calorie energy drinks.
The team measured the fat cells in different areas of the body before and after the experiment.
Dr Jensen said: "The cellular mechanisms are different.
"The accumulation of abdominal fat happens largely by individual cells expanding in size, while with fat gain in the femoral or lower body, it's the number of fat cells that increases. So, different mechanism, different impact."
Dr Jensen said the findings, published in the Proceedings of the National Academy of Sciences, challenge the idea that the number of fat cells remains stable in adults. On average the participants put on 2.5kg of upper body fat and 1.5kg of lower body fat.
Cathy Ross, senior cardiac nurse at the British Heart Foundation, said: "This small study supports what we already know about the harmful link between the location of fat in our bodies and the increased risk of heart disease, cancer and type 2 diabetes.
"We cannot choose where we store our fat and some people are more likely to put weight on around their middle than others. But it is important to remember that you can be a 'healthy' weight and still have a large waistline, putting your heart health at risk.
"Making small sustainable changes to our lifestyles can help us keep our weight and waistlines in check - and in doing so, help to reduce our risk of serious illnesses."