Type 2 diabetes rates are increasing rapidly in the U.S. and worldwide. Our love of processed food and sugary drinks are two behaviors contributing to this rise, and now there's a third: eating two or more servings of red meat every week can raise your risk of diabetes considerably.

Diabetes is not only a serious health burden on its own, it is also a major risk factor for cardiovascular disease, kidney disease, cancer and dementia.

People who ate the most red meat had a 62 percent higher risk of developing type 2 diabetes compared to those who ate the least.

Information on the diets of over 216,000 participants in three long-term studies — the Nurses' Health Study (NHS), NHS II, and Health Professionals Follow-up Study (HPFS) — was used in the research conducted by Harvard T.H. Chan School of Public Health. Participants filled out questionnaires on how frequently they ate a variety of foods every two to four years, for up to 36 years.

More than 22,000 participants developed type 2 diabetes over the study period.

People in the study who ate red meat the most often had a 62 percent higher risk of developing type 2 diabetes compared to those who ate the least. Every additional daily serving of processed meat was associated with a 46 percent greater risk of developing type 2 diabetes. Every additional daily serving of unprocessed red meat was associated with a 24 percent rise in risk.

“Our findings strongly support dietary guidelines that recommend limiting the consumption of red meat, and this applies to both processed and unprocessed red meat,” said first author Xiao Gu, postdoctoral research fellow in the Department of Nutrition.

A link between red meat consumption and type 2 diabetes risk had been seen in previous studies, but this study, which analyzed a large number of type 2 diabetes cases among participants being followed for an extended period of years, adds a greater level of certainty about the association.

Every additional daily serving of unprocessed red meat was associated with a 24 percent rise in risk.

“Given our findings and previous work by others,” senior author Walter Willett, professor of epidemiology and nutrition, said, “a limit of about one serving per week of red meat would be reasonable for people wishing to optimize their health and wellbeing.”

Need help replacing meat-based meals in your diet? The researchers estimated the potential effects of substituting one daily serving of red meat for another protein source. In addition to the option of eating more chicken and fish, they found that substituting a serving of nuts or legumes was associated with a 30 percent lower risk of type 2 diabetes, and substituting a serving of dairy products was associated with a 22 percent lower risk.

The study is published in the American Journal of Clinical Nutrition.