Red Meat Linked to Increased Risk of Type 2 Diabetes

A new study by Harvard School of Public Health (HSPH) researchers finds a strong association between the consumption of red meat—particularly when the meat is processed—and an increased risk of type 2 diabetes. The study also shows that replacing red meat with healthier proteins, such as low-fat dairy, nuts, or whole grains, can significantly lower the risk.

The study, led by An Pan, PhD, a research fellow in the HSPH department of nutrition, was published online in the American Journal of Clinical Nutrition.

Researchers analyzed questionnaire responses from 37,083 men followed for 20 years in the Health Professionals Follow-Up Study; 79,570 women followed for 28 years in the Nurses' Health Study I; and 87,504 women followed for 14 years in the Nurses' Health Study II. They also conducted an updated meta-analysis, combining data from their new study with data from existing studies that included a total of 442,101 participants, 28,228 of whom developed type 2 diabetes during the study. After adjusting for age, BMI, and other lifestyle and dietary risk factors, the researchers found that a daily 100-g serving of unprocessed red meat (about the size of a deck of cards) was associated with a 19% increased risk of type 2 diabetes. They also found that one daily serving of half that quantity of processed meat—50 g (for example, one hot dog or sausage or two slices of bacon)—was associated with a 51% increased risk.

The researchers found that, for an individual who eats one daily serving of red meat, substituting one serving of nuts per day was associated with a 21% lower risk of type 2 diabetes; substituting low-fat dairy, a 17% lower risk; and substituting whole grains, a 23% lower risk.

Based on these results, the researchers advise that consumption of processed red meat should be minimized and unprocessed red meat should be reduced. If possible, they add, red meat should be replaced with healthier choices, such as nuts, whole grains, low-fat dairy products, fish, or beans.

"Our study clearly shows that eating both unprocessed and processed red meat—particularly processed—is associated with an increased risk of type 2 diabetes," says Pan. He noted that the 2010 U.S. dietary guidelines continue to lump red meat together with fish, poultry, eggs, nuts, seeds, beans, and soy products in the "protein foods" group. But since red meat appears to have significant negative health effects, Pan suggested the guidelines should distinguish red meat from healthier protein sources and promote the latter instead.

Source: Harvard School of Public Health