A big bottom and thighs could be your insurance to longevity. Too much abdominal fat seems to up the risk of heart disease, stroke and diabetes, while piling on the pounds around rear and top of the legs lowers it.
So Michael Jensen of Mayo Clinic in Rochester, Minnesota, in the US and colleagues overfed a group of men and women for eight weeks to see how fat grew in their bodies, reports the journal Proceedings of the National Academy of Sciences.
They measured body fat before and after and found on average participants put on 5.5 pounds of upper-body fat and 3.3 pounds of lower body fat, according to the Daily Mail.
But there was a striking difference in that fat cells around the stomach and heart grew in size but not in number by producing more fat-synthesising proteins.
The reverse was true for thigh fat cells, which increased in number -- but did not get bigger.
Jensen said the findings challenge the concept that the number of fat cells in the body remains stable in adults.
They also support the idea that increased capacity to produce lower-body fat cells creates some form of protection to the upper body and potentially helps prevent disease.
The latest findings could help to explain the benefits of having a pear-shaped body.
In future, drugs that alter the way fat is stored around the body could be used to combat heart and other diseases.
Last year a Danish study of 3,000 people showed men and women with thighs more than 23.6 inches in circumference have a lower risk of heart disease.