Study links processed red meat to type 2 diabetes

A daily 100-gram serving of unprocessed red meat may increase the risk of developing type 2 diabetes by 19%, while just 50 grams of processed red meat – for example one hot dog, a sausage, or two slices of bacon – is associated with a 51% increased risk of diabetes, according to research from the Harvard School of Public Health.

The authors, led by An Pan from Harvard, added that replacing red meat with healthier proteins, such as low-fat dairy, nuts, or whole grains, can significantly lower the risk.

“Clearly, the results from this study have huge public health implications given the rising type 2 diabetes epidemic and increasing consumption of red meats worldwide,”​ said Frank Hu, professor of nutrition and epidemiology at Harvard.

“The good news is that such troubling risk factors can be offset by swapping red meat for a healthier protein,”​ he added.

Study details​

Writing in the American Journal of Clinical Nutrition​, Pan and colleagues conducted an updated meta-analysis, combining data from their new study with data from existing studies that included a total of 442,101 participants.

They analyzed data 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.

After adjusting for age, body mass index (BMI), and other lifestyle and dietary risk factors, the researchers found that a daily 100-gram serving of unprocessed red meat was associated with a 19% increased risk of type 2 diabetes, whilst processed red meats were found to raise the risk by 51%.

Pan and his team also 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.

“Eating both unprocessed and processed red meat – particularly processed – is associated with an increased risk of type 2 diabetes,”​ said Pan.

He noted that current dietary guidelines continue to group red meats together with fish, poultry, eggs, nuts, seeds, beans, and soy products as ‘protein foods.’

However, since red meat appears to have significant negative health effects, including an increased risk of diabetes, cardiovascular disease, and even total mortality (as suggested by several recent studies), Pan suggests that guidelines should distinguish red meat from healthier protein sources and promote the latter instead.

“From a public health point of view, reduction of red meat consumption, particularly processed red meat, and replacement of it with other healthy dietary components, should be considered to decrease type 2 diabetes risk,”​ concluded the researchers.

Source: American Journal of Clinical Nutrition​
Published online ahead of print, doi: 10.3945/​ajcn.111.018978
“Red Meat Consumption and Risk of Type 2 Diabetes: 3 Cohorts of U.S. Adults and an Updated Meta-Analysis,"​
Authors: A. Pan, Q. Sun, A.M. Bernstein, M.B. Schulze, J.E. Manson, W.C. Willett, F.B. Hu