Type 2 diabetes is becoming increasingly widespread throughout the world and lifestyle habits, such as exercise and nutrition, are the biggest culprits.

In a bygone era, high-cholesterol diets were epidemiologically linked to disturbances in glucose metabolism and therefore type 2 diabetes, so eggs were a no-no, but actual experimental studies instead showed the consumption of eggs has led to improved glucose balance, among other things.  What does that mean for eggs? There haven't been many population-based studies on the association between egg consumption and type 2 diabetes and findings were inconclusive. Egg consumption was associated with an elevated risk or nothing at all. 

 A new study found that egg consumption was associated with a lower risk of type 2 diabetes as well as with lower blood glucose levels. The dietary habits of 2,332 men aged between 42 and 60 years were assessed at the baseline of the Kuopio Ischaemic Heart Disease Risk Factor Study, KIHD, at the University of Eastern Finland in 1984-1989.

During a follow-up of 19.3 years, 432 men were diagnosed with type 2 diabetes. 

Men who ate approximately four eggs per week had a 37 percent lower risk of type 2 diabetes than men who only ate approximately one egg per week. This association persisted even after possible confounding factors such as physical activity, body mass index, smoking and consumption of fruits and vegetables were taken into consideration. The consumption of more than four eggs did not bring any significant additional benefits.

A possible explanation is that unlike in many other populations, egg consumption in Finland is not strongly associated with unhealthy lifestyle habits such as smoking, low physical activity or consumption of processed meats. In addition to cholesterol, eggs contain many beneficial nutrients that can have an effect on, for example, glucose metabolism and low-grade inflammation, and thus lower the risk of type 2 diabetes. The study also suggests that the overall health effects of foods are difficult to anticipate based on an individual nutrient such as cholesterol alone. Indeed, instead of focusing on individual nutrients, nutrition research has increasingly focused on the health effects of whole foods and diets over the past few years.

Citation: Jyrki K. Virtanen, Jaakko Mursu, Tomi-Pekka Tuomainen, Heli E.K. Virtanen, Sari Voutilainen, 'Egg consumption and risk of incident type 2 diabetes in men: The Kuopio Ischaemic Heart Disease Risk Factor Study', American Journal of Clinical Nutrition, April 2, 2015.