As if you need another reason not to eat red meat. A new study-- from researcher An Pan Ph.D. of the National University of Singapore--published in the gold-standard JAMA (Journal of the American Medical Association) establishes a robust link between eating red meat and developing adult-onset diabetes (known as type-2 diabetes mellitus), which is the seventh leading cause of death in the U.S.--ranked just behind Alzheimer's and fatal accidents.
Nitrosamines, found in hot dogs and other processed meats, might be contributing to a diabetes epidemic.
By digging into reams of data from the massive long-term Harvard group studies, Pan was able to analyze health stats from 149,000 American men and women representing 1.9 million "person years" of follow-up. In research terms this is a powerful study.
What's intriguing is that Pan was able to tease out a group of people who increased their red meat intake over time and compare them to people who did not increase intake.
Increasing red meat intake by just a half a serving a day increased the risk of developing type-2 diabetes by a whopping 48% over a four year period.
A retrospective study like this can not offer clues as to why red meat is linked to diabetes, but experts do have a few thoughts. In the accompanying JAMA commentary, William J. Evans, Ph.D. of GlaxoSmithKline and Duke University suggests the problem lies in saturated fat. It's well known that being overweight is strongly associated with diabetes, however, in Pan's study, the results held regardless of weight gain--people who gained weight by increasing red meat consumption had higher rates of type-2 diabetes onset than people who gained weight by eating other foods. Others say the link is possibly due to a case of iron overload, which sets the stage for insulin resistance.
But we think the most interesting hypothesis comes from David Nathan, M.D., professor of medicine at Harvard and director of the Diabetes Center at Massachusetts General Hospital. Nathan told NPR that the compound nitrosamine found in red meat might be causing the problem.
"Our understanding is that especially processed meats include nitrosamine, which can cause inflammation associated even with some poisoning of the cells that make insulin," he told NPR's Allison Aubrey.
Nitrosamine, which is also linked to cancer, is present in many foods, but at highest levels in processed meats like hot dogs, bacon and lunch meats. Considering that in just a single day, on July 4, Americans will consume 150 million hot dogs--enough to stretch from D.C. to L.A. over five times!--it is no wonder that type 2 diabetes is at epidemic levels.