The study, which could lead to new treatments for obesity, was published online April 21, 2010, in the American Chemical Society's Journal of Proteome Research. Dr. Jong Won Yun, from the department of biotechnology, Taegu University (Kyungbuk, South Korea) and colleagues point out that obesity is a major public health threat worldwide, linked to diabetes, high blood pressure, heart disease, and other health problems. Laboratory studies have suggested that capsaicin may help fight obesity by decreasing calorie intake, shrinking fat tissue, and lowering fat levels in the blood. Nobody, however, knows precisely how capsaicin might trigger such beneficial effects.

In an effort to find out, the scientists fed high-fat diets with or without capsaicin to lab rats used to study obesity. The capsaicin-treated rats lost 8% of their body weight and showed changes in levels of at least 20 key proteins found in fat. The altered proteins work to break down fats. "These changes provide valuable new molecular insights into the mechanism of the anti-obesity effects of capsaicin,” the scientists reported.