Justin Sullivan/Getty Images

Baby got back! Good news not only for J. Lo and Sir Mix-a-Lot fans. According to a new study, having some junk in your trunk can be healthy. Research at the University of Oxford and Churchill Hospital shows that the assumption that leaner is always better may be literally ass backward. In the past, medical experts believed that the healthiest people were those with overall low body fat compared to those with too much butt fat or belly fat. But when a team studied the health effects of fat distribution, they found that having a predominance of body fat in the thighs and backside, known as gluteofemoral fat, has significant health benefits.

Gluteofemoral fat is measured by thigh circumference, hip circumference and fat deposits on the legs. This type of lower-body fat storage takes more time to accumulate and is harder to break down than upper-body fat. The report says that the protective effects of lower-body fat distribution, which is typical of a pear-shaped body type, has been confirmed across the board and in people with a wide range of age, weight and health status. The researchers are still working out exactly how and why the benefits exist, but it appears that lower-body fat secretes a compound that mops up fatty acids and traps harmful fatty particles. The study went even further to assert that this type of fat is "protective" against diabetes, heart disease and other conditions associated with obesity.

This isn't the first time we've heard that all fat is not created equal. Previous findings have shown how body shape may play a significant role in health. Fat distribution can be a predictor for risk of certain diseases, and belly fat is the most dangerous. It's the stuff that's packed around (and often in) your internal organs, including your heart, so it's been dubbed "heart attack fat." And unlike fatty tissue in other parts of your body, these fat cells are not just lying around as dormant energy waiting to be burned up. Instead, this dynamic fat metabolically active and is damaging your health by continually pumping artery-clogging fatty acids into your bloodstream. These fat cells also produce hormones and can promote insulin resistance, a precursor to Type 2 diabetes, and can cause you to secrete estrogen after menopause, which may increase your breast cancer risk.

Although lower-body fat may be healthier than upper-body fat, most people don't have much control over where their body decides to store its unburned calories. It's largely a matter of genetics. The fact that your body shape might be inherited doesn't turn your BMI (body mass index) into Blame Mom Indefinitely. Whether a pear or an apple shape, regular exercise and a sensible diet will always be essential to good health.

Sounds depressing. I'll have to side with The Today Show's Dr. Nancy Snyderman. When asked for her opinion on the report, she went vice presidential, and said "This is where I get to join Joe Biden's club and say, give me a f***ing break."


Alicia Villarosa is a regular contributor to The Root.

Become a fan of The Root on Facebook. Follow us on Twitter.