With more than two million Canadians now suffering from diabetes and rates expected to climb dramatically in the next several years, prevention of diabetes is an important public health issue. As those concerned about diabetes know healthy nutrition is a key aspect of effective prevention. With such wide consumption, there has been much interest in whether coffee has a negative or positive effect on prevention of diabetes.

The current body of evidence indicates that coffee consumption plays a role in preventing the onset of diabetes, although diabetes prevention is complicated and involves a range of lifestyle factors.

The majority of major studies in recent years have shown that coffee can cut diabetes risk quite significantly – by up to 30 per cent.

What is less understood is how this works. Some experts explain that the antioxidants in coffee, specifically caffeic and chlorogenic acids, have a protective effect. It has also been theorized that coffee works to cut insulin resistance, a precursor to diabetes, by helping to ease the delivery of insulin to the body’s tissues.


While there is an extensive body of research supporting the role of coffee in diabetes prevention, in recent years two major studies have emerged as most definitely confirming this positive connection.

In one of the largest coffee and diabetes studies ever conducted, researchers at the Harvard School of Public Health followed men and women in the Nurses health Study and Health Professionals’ Follow up Study for more than ten years. Published in the Annals of Internal Medicine (reference link) in 2004, the study was designed to isolate the effect of coffee, with results adjusted to offset other risk factors such as age, weight and exercise. Significantly, men’s risk of developing diabetes was cut by half and women by 30 per cent. The most dramatic results were shown at high consumption levels of six cups, but positive results were seen even with moderate consumption.

Another major research study conducted in Finland and published in the Journal of the American Medical Association(reference link) in 2004, showed similar results. Women who drank three to four cups daily cut their risk by 29 per cent while men cut risk by 27 per cent. At high rates of coffee consumption of 10 cups or more, the rates increased to 80 per cent for men and 55 per cent for women.

My doctor tells me if I don’t get my weight down I could develop type 2 diabetes and I am worried. Should I make changes to what I am eating and drinking?

Check out Canada’s Food Guide to Healthy Eating. The best approach is to eat sensibly with a focus on fruits and vegetables, lean proteins and whole grains. Get plenty of fluids, with several glasses of water each day, and stay away from sugary juices and sodas. No need to give up coffee in moderate amounts though. In fact, research shows that daily coffee consumption could cut your diabetes risk by as much as 30 per cent.