NEW YORK — Does the body put on fat in actual layers, or does fat accumulated today mix with the fat stored away years ago?
“Fat is deposited diffusely and not in layers,” said Louis J. Aronne, director of the comprehensive weight control center at New York-Presbyterian/Weill Cornell Medical Center. “It is added to fat cells that already contain fat and expands them.”
If weight is gained rapidly, Aronne said, new fat cells may be made, but they do not accumulate in layers.
“If subcutaneous fat stores cannot accept all the fat for genetic, medical or other reasons,” he said, “more of it winds up inside the abdomen, where it presents a greater metabolic risk because it is in the circulation of the liver.”
A 2008 study in the journal Nature found that the number of fat cells in the body is set in childhood and early adolescence and stays constant evenafter significant weight loss, for lean and obese people.
“This explains why it’s so difficult to lose weight,” Aronne said. “When fat cells shrink, levels of a fat-cellhormone, leptin, drop faster than fat mass is reduced. This tricks the brain into thinking you’ve lost more weight than you actually have. It’s also interesting that fat cells don’t live forever, but the number somehow remains constant.”
ActiveStyle, Pages 23 on 02/28/2011