Scientists discover amino acid switch that turns fat into a calorie-burning furnace

Researchers discovered that restricting the amino acid cysteine causes white fat cells to convert into energy-burning brown fat cells, leading to significant weight loss. The finding emerged after scientists noticed reduced cysteine levels in fat tissue of participants who cut calories in the CALERIE trial, and confirmed in animal studies that cysteine restriction triggered fat browning without tissue damage—potentially offering new weight management approaches beyond calorie counting.