Researchers at Harvard Medical School in the U.S. suggest that having a big bum may be a good thing from a health perspective.
It appears that the type of fat that accumulates around the hips and bottom may offer some protection against diabetes.
Experts know that fat that collects in the abdomen, known as visceral fat, can raise a person's risk of diabetes and heart disease, whereas people with pear-shaped bodies, with fat deposits in the buttocks and hips, are less prone to these disorders.
Visceral and subcutaneous fat have major genetic differences and differ in their exposure to various hormones and growth factors and in their nutrient and oxygen supply.
The subcutaneous fat which collects under the skin possibly helps to improve sensitivity to the hormone insulin, which regulates blood sugar and may be actively protecting people from metabolic disease.
According to Dr. Ronald Kahn who led the research, mice given transplants of this type of fat deep into their abdomens lost weight and their fat cells shrank, even though they made no changes in their diet or activity levels.
Dr. Kahn says surprisingly it had a beneficial effect especially when it was placed inside the abdomen.
Dr. Kahn says initially the study aimed to find out why fat located in different parts of the body seems to have different risks of metabolic disease such as diabetes so they conducted a series of experiments on mice where they transplanted subcutaneous fat from donor mice into the bellies and under the skin of mice.
Mice that were given subcutaneous fat transplanted into their bellies started to slim down after several weeks, and also showed improved blood sugar and insulin levels compared to mice that underwent a sham procedure.
Dr. Kahn says this is an important result because not only does it say that not all fat is bad, but it points to a special aspect of fat where more research is needed.
The team are trying to find the substances produced in subcutaneous fat that provide the benefit as this could lead to the development of new drugs which mimic this effect.
Kahn says none of the known hormones appeared to be involved in this process and their findings suggest that there is some good fat.
The study is published in the current issue of Cell Metabolism.