Obesity: A ‘natural’ way to burn off calories

A plant-derived molecule called berberine can help rodents burn off excess calories by increasing the activity of brown fat, a study in Nature Communications reports this week. Brown fat plays an active role in energy expenditure by metabolising fatty acids and generating heat.

The compound, berberine, is found in various plants used as herbal remedies, including some used in traditional Chinese medicine. Berberine has previously been found to have a variety of metabolic benefits, including anti-diabetic and cholesterol-lowering effects.

Guang Ning and colleagues report that berberine increases energy expenditure, limits weight gain, improves cold tolerance and enhances brown adipose tissue activity in genetically obese mice and in mice that consume a high-fat diet. They find that it does this by activating two types of fat tissue - brown fat and so-called beige fat - that burn off calories by producing heat. The work establishes a new mechanism of action for the potentially beneficial metabolic effects exerted by berberine; whether this mechanism also works in humans remains to be tested.