When Fat Makes You Healthy: Subcutaneous Fat May Produce Beneficial Hormones
May 22, 2008
It has long been known that type 2 diabetes is linked to obesity, particularly fat inside the belly. Now, researchers at the Joslin Diabetes Center have found that fat from other areas of the body can actually reduce insulin resistance and improve insulin sensitivity.
In a study published in the May issue of Cell Metabolism, a team lead by C. Ronald Kahn, M.D., found that subcutaneous fat—fat below the skin (usually in the hips and thighs)—is associated with reduced insulin levels and improved insulin sensitivity.
Kahn says that fat in the belly increases the risk of diabetes and mortality and it has been suggested that obesity in subcutaneous areas, often the hips and thighs, might decrease such risks.
His study concludes that fat under the skin is intrinsically different from visceral fat (belly fat or fat packed in between organs) and may produce substances that can improve glucose metabolism.
“The surprising thing was that it wasn’t where the fat was located,” Kahn said. “It was the kind of fat that was the most important variable. Even more surprising, it wasn’t that belly fat was exerting negative effects, but that fat under the skin was producing a good effect. Animals with more of this kind of fat didn’t gain as much weight as they aged, had better insulin sensitivity, lower insulin levels, and were improved all around.”
In addition, Kahn noted that a class of diabetes drugs called thiazoladinediones (ACTOS, Avandia) may cause patients to gain weight in the subcutaneous area, yet also improve insulin sensitivity.
Kahn said it is possible that fat underneath the skin may be producing certain hormones, known as adipokines, that produce beneficial effects on metabolism. These effects may offset the negative effects produced by belly fat.