The Belly Fat Battle

Visceral fat differs from subcutaneous fat in that it releases fatty acids and inflammatory substances directly into the liver rather than into the general circulation. Some experts believe this may play a direct role in causing the diseases linked to abdominal obesity. But not everyone agrees. Samuel Klein, who heads the Center for Human Nutrition at the Washington University School of Medicine in St. Louis, has published data showing that key factors in those diseases—such as insulin sensitivity and triglyceride levels—are more tightly linked to the amount of fat inside the liver rather than outside it, although the two tend to track one another.