Few can say no to a cup of hot cocoa on a cold winter’s night. “Enjoy!” say Penn State researchers. They have found that a little bit of cocoa may be a powerful diet aid in helping to control inflammation and ameliorate related diseases, including diabetes. Numerous current studies link obesity to inflammation in the body.

Cocoa, although a common ingredient of chocolate, by itself has low-calorie, low-fat and high-fiber content. The researchers fed laboratory mice the human equivalent of 10 tablespoons of cocoa powder—about four or five cups of hot cocoa—along with a high-fat diet for 10 weeks. The control group ate the same diet without the cocoa.

Lead researcher Joshua Lambert, Penn State associate professor of food science, says the study results surprised the team, which did not expect the “dramatic reduction of inflammation and fatty liver disease” associated with obesity. Although the animals lost no weight, the cocoa powder supplement reduced liver triglycerides by 32 percent and plasma insulin levels by 27 percent, indicating it might be a powerful obesity-fighting tool.

But there is a catch: Adding sugar, an inflammatory substance in itself, to healthy cocoa will likely neutralize the benefits. Try stevia as a sweetener instead; it’s been used for decades to lower blood sugar.