Full confession: I love to read about brown fat, a relatively newly discovered form of fat that burns calories directly. Brown fat might be the key to weight loss, writes Alice Park, who covers breaking health news for TIME magazine. Last week, she published, Why Brown Fat May Be the Key to Weight Loss. Kudos to TIME for covering valuable research (when others did not.) But there’s a lot more to add. First, some words about brown fat.
The body makes two kinds of fat: white fat, familiar to all, the storage form of energy, and brown fat that is not stored but burned directly as fuel. When triggered by exposure to the cold, brown fat generates heat (white fat just sits there). Hibernating animals produce brown fat to stay warm during the winter. Newborn babies have lots of brown fat, their own little furnaces, to protect against the cold. We used to think that adults could not make brown fat, but now we know everyone can turn white fat into brown when there is need.
The TIME article reports on research published in the October 9th issue of the journal Cell, completed by Xiaoyong Yang and his team at the Yale School of Medicine. The group studies the neurobiology of metabolism, which is how neurons in the brain regulate the relationship of calories in to calories out. In his new study on mice, Yang discovered a single molecular process that controls both hunger and brown fat production. These hunger signals produce biochemical changes that announce to the brain that it’s time to regulate which type of fat to burn. When those hunger signals don’t work (presumably because they’ve been overridden by constant overeating), mice don’t make brown fat and so they don’t burn calories as well. Hunger is intimately tied to energy conservation.
TIME might want to change their title to, Why Hunger Management May Be the Key to Weight Loss. My take is that this bodes well for the practice of intuitive eating. Since fasting and voluntary “dieting” reduce calorie burning, it doesn’t make sense to go hungry or to overeat. Trust the wisdom of the body to maintain healthy weight.