Using human stem cells, the team generated a technique to screen for compounds that are able to achieve this important feat of fat colour transfer and have already identified two of these compounds.

New discoveries in creating brown fat cells could make it a lot easier to get in shape for your next vacation. © Wallenrock/shutterstock.com

While it’s not certain how the no-more-treadmill-pill would be concocted and whether it would be safe and effective, it’s an important first step in the fight against obesity.

That fat cells can be converted is well-known. For example, a study at the University of Montreal [1] identified retinoic acid-a derivative of Vitamin A-as being able to turn fat cells brown in mice, but the Harvard team says their discovery is more significant. "What we were really impressed by is that there are some compounds that have this same kind of effect when they are administered to animals, but when you remove them, the effect goes away,” says Chad Cowan, a principal faculty member of HCSI. "But what we saw here was a stable conversion."

Still, says Cowan, it’s not certain what the long term effects on the metabolism and immune system could be, although he is encouraged by the success of the two compounds in mice.

Brown fat is considered the "good fat" because unlike white fat, it’s capable of generating heat by oxidizing fatty acid. To ignite this process, no exercise is necessary on the part of the individual, so brown fat cells increase the basal, or resting, metabolism.

Researchers have come to believe that differing proportions of brown fat could explain why some eat more than others without gaining weight and without considerable exercise efforts. Other studies have indicated that it’s possible to create brown fat in human participants by keeping their living environment at a cool 19 degrees C (66F) for a minimum of one month [2].

The HSCI study was published in the journal Nature Cell Biology. [3]