Daily dose of dark chocolate may lower diabetes risk, study finds

Eating a few servings of dark chocolate each week has been found to reduce the risk of Type 2 diabetes.

People who ate at least five servings of dark chocolate per week had a 21% lower risk of developing Type 2 diabetes compared to people who ate dark chocolate rarely, if ever, according to a study published Wednesday in the British Medical Journal.

Eating more dark chocolate servings per week seemed to only help. Researchers found a 3% lower risk of Type 2 diabetes for each additional weekly serving of dark chocolate.

Milk chocolate showed no similar benefit, according to the study, which analyzed the health data of more than 190,000 health care professionals in the United States for over 30 years.

Instead, the study showed, eating milk chocolate at a similar rate was associated with long-term weight gain, a key risk factor for Type 2 diabetes.

Tens of millions of people in the U.S. have Type 2 diabetes, a disease in which the body cannot use insulin properly, according to the Centers for Disease Control and Prevention.

Most cases of Type 2 diabetes can be prevented through lifestyle changes including maintaining a healthy weight and being physically active, according to the CDC.

Once diagnosed with Type 2 diabetes, a person can face complications ranging from heart disease and stroke to nerve and eye damage, foot problems and skin conditions.

It is unclear exactly why dark chocolate affects the risk of Type 2 diabetes. The study's authors suggested the higher cocoa content in dark chocolate may be one reason, as the "bioactive compounds" found in cocoa can help improve insulin sensitivity and boost glucose metabolism, among other benefits.

The researchers noted that while dark chocolate contains sugar and saturated fat like milk chocolate, it also has "rich polyphenols" that can counteract those ingredients and their affect on weight gain.

Dr. Niki Iranpour, a member of the ABC News Medical Unit, contributed to this report.