Dietary Patterns and the Risk for Type 2 Diabetes in U.S. Men

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The summary below is from the full report titled "Dietary Patterns and Risk for Type 2 Diabetes Mellitus in U.S. Men." It is in the 5 February 2002 issue of Annals of Internal Medicine (volume 136, pages 201-209). The authors are RM van Dam, EB Rimm, WC Willett, MJ Stampfer, and FB Hu.

What is the problem and what is known about it so far?

Type 2 diabetes mellitus, the most common form of diabetes, interferes with the body's ability to store foods, resulting in high blood levels of sugar. Over time, high blood sugar levels lead to complications such as blindness, kidney failure, and heart disease. Being overweight and physically inactive increases a person's chances of developing type 2 diabetes. Diet probably affects the risk for this disease, but it is difficult to separate the risk of diet from the risks of being overweight and inactive. Moreover, previous studies of diet and diabetes have given a narrow view of diet and diabetes because these studies focused on individual food components instead of the balance between different types of foods (dietary patterns).

Why did the researchers do this particular study?

To examine the association between dietary patterns and the development of type 2 diabetes.

Who was studied?

42,504 U.S. health professionals, all men aged 40 to 75 years who did not have diabetes, heart disease, or cancer when the study began in 1986.

How was the study done?

Study participants completed three dietary surveys about how often they ate particular foods. On the basis of this information, researchers scored each man's diet according to how "western" or "prudent" it was. Western diets are high in red and processed meats, dairy products, refined grains, and sweets. Prudent diets are high in vegetables, fruit, fish, poultry, and whole grains. The researchers also collected information on body size and physical activity and followed the men for 12 years to see who developed type 2 diabetes.

What did the researchers find?

1321 participants developed type 2 diabetes. By comparing men of similar body size and physical activity, the authors showed that men with high prudent-diet scores were less likely to develop diabetes than were men with low prudent-diet scores. On the other hand, men with high western-diet scores were more likely to develop diabetes than were men with low western-diet scores. Men with high western-diet scores and low physical activity were twice as likely as men with low western-diet scores and high physical activity to develop diabetes.

What were the limitations of the study?

Most of the men in this study were white. The results may not apply to women or to men in other ethnic groups.

What are the implications of the study?

To decrease their chances of getting type 2 diabetes, men should increase their intake of vegetables, fish, poultry, and whole grains and limit intake of red meat, processed meat, high-fat dairy foods, refined grains, and sweets.