Not all fat is created equal, especially on our bodies. Fat that accumulates around the belly and internally, known as visceral fat, is the most unhealthy type. It has been shown to increase the risk of heart disease and other conditions. But you don't have to resign yourself to a growing midsection: a new study suggests that fighting fat with fat can help whittle your middle — you just have to choose the right kind.
The Swedish study, published in the journal Diabetes , looked at a group of 39 men who were put on a diet that included an extra 750 calories a day. Half of the men got those calories from muffins made with saturated fat  (palm oil), while the other half were fed muffins made with sunflower oil, a polyunsaturated fat. Other than this difference, each group ate the same amounts of sugar, carbs, fat, and protein.
After seven weeks, researchers found that both groups gained weight, but the difference in each group's body compositions were surprising. The palm oil group gained most of their weight in their bellies and around internal organs, while the sunflower oil group gained less belly fat than the palm oil group — and their weight gain actually included an increase in muscle mass as well.
While more research is necessary, the study's authors believe that eating more polyunsaturated fats can turn on genes that increase sugar metabolism as well as reduce fat storage in the body . Saturated fats, on the other hand, may do the opposite by encouraging your body to store excess fat in the abdomen. A smaller waistline and more metabolism-boosting muscles: more proof that you should make healthy unsaturated fats  — like those found in olive oil, avocado, and nuts — a mainstay in your diet. Limit saturated fats like butter — this guide of baking substitutes for butter  can help!