It may be possible to convert dangerous visceral white fat into fat-burning brown fat, according to a new Harvard University study. Scientists blocked an enzyme that helps control cell’s creation and activity called Aldh1a1 in the white fat cells of mice, making the white fat cells behave like fat-burning brown fat cells. “We have discovered a pathway that controls whether fat will be white or brown and it can be manipulated, especially in the visceral fat,” says senior study author Jorge Plutzky. “It’s proof of concept. It’s conceivable that this might be a way to target visceral fat in humans.” Studies showed lower weights and blood sugar levels in both mice bred without the enzyme or in mice where the enzyme was inhibited. The enzyme, produced when the body breaks down vitamin A, is concentrated in visceral fat surrounding the organs. The researchers are working to develop therapies that target this enzyme. In January, scientists showed that the hormone irisin, released during exercise, also helps convert white fat to brown fat, as does exposure to cold.