Shivering, exercise burn same amount of fat

New Delhi : Shivering in cold amounts to the same amount of fat loss as the body does during exercise, finds a study.

Researchers at the Joslin Diabetes Center, Harvard, and the Ohio State University have identified a fat molecule that circulates in body after workout. This lipid, released by so-called brown fat, helps in improving cardiovascular health, and regulate weight.

Now according to a study, published on May 1 in the journal Cell Metabolism, found that exercise increases the levels of a lipid called 12,13-dihydroxy-9Z-octadecenoic acid (12,13-diHOME) in male, female, young, old, sedentary, and active human subjects. Interestingly, same increase was noted while people were left shivering in the cold.

"Our data provide some of the first evidence that exercise can alter the endocrine function of brown fat by increasing 12,13-diHOME," says co-author Laurie Goodyear, senior investigator at the Joslin Diabetes Center and associate professor at Harvard Medical School. "These data highlight another mechanism for the beneficial effects of exercise."

The lipid 12,13-diHOME is produced by brown adipose tissue (BAT), or brown fat. Brown fat, which burns more calories than the white fat linked to type 2 diabetes and heart disease, has been called the "good" fat. Newborns burn a reserve of brown fat to stay warm, but the purpose of the few grams of brown fat that adults retain is unclear.

While cold exposure is known to stimulate BAT, previous studies have shown that exercise decreases BAT activity in humans and rodents. "Most data suggests that cold and exercise have opposite effects on BAT, so to see that 12,13-diHOME was released from BAT after both exercise and cold exposure was unexpected," says co-author Kristin Stanford of the Ohio State University's Wexner Medical Center.