Fat on the hips, thighs and bum, rather than around the waist, has a range of health benefits and actively protects against diabetes and heart disease, researchers at Oxford University said.
"Fat around the hips and thighs is good for you but around the tummy is bad," said Dr Konstantinos Manolopoulos, one of three scientists behind the research which has been published in the International Journal of Obesity.
A big bottom is much better than carrying fat around the waist, which tends to release more harmful fatty acids into the body, the research shows.
Belly fat also releases molecules called cytokines which trigger inflammation - raising the risk of diabetes and heart disease.
But fat carried on the thighs traps these harmful fatty acids and stops them from latching on to the liver and muscles and causing range of health problems, including insulin resistance.
Although fat around the thighs and backside tends to burn slower and be harder to shift, it can release beneficial hormones which protect the arteries and help blood sugar control, the research showed.
Manolopoulo says that the idea that body fat distribution is important to health has been known for some time.
"However is it only very recently that thigh fat and a larger hip circumference have been shown to promote health, that lower body fat is protective by itself."
It is shape that matters - and as far as health is concerned, being 'pear-shaped' is much preferable to being 'apple-shaped'.
In an ideal world, the more fat around the thighs the better - as long as the tummy stays slim, Manolopoulos said.
"Unfortunately, you tend not to get one without the other," he added.
AFP has contributed to the report.