High Red Meat Consumption Linked to Increased Diabetes Risk

Individuals who routinely eat high amounts of red meat may have a higher risk of developing type 2 diabetes (T2D), according to new research published in The American Journal of Clinical Nutrition.

This finding applies to red meat in general, including both processed and unprocessed meat, though processed meat was linked to an even higher risk of T2D.

Steak on cutting board | Image Credit: Rishieka – stock.adobe.com

Processed red meats include but are not limited to:

• Beef or pork hot dogs
• Cured bacon
• Beef jerky
• Processed meat sandwiches
• Other processed meats such as sausage and salami

Unprocessed red meats include but are not limited to:

• Lean, extra lean, or regular hamburger meat
• Fresh beef, pork, or lamb as a main dish or in a sandwich or mixed dish

The findings of this prospective cohort study are based on research including more than 200,000 participants from the Nurses’ Health Study (NHS), NHS II, and Health Professionals Follow-up Study (HPFS), with nearly 5.5 million person-years of follow-up. Red meat intake was determined using semiquantitative food frequency questionnaires (FFQs) conducted every 2 to 4 years since each study’s baseline, and researchers estimated the associations between red meat consumption and T2D risk using multivariable-adjusted proportional hazards.

When comparing the highest and lowest quintiles of consumption, the researchers found that intake of total, processed, and unprocessed red meat were positively and approximately linearly associated with increased T2D risk. Total red meat consumption was nearly 2 servings per day on average for the highest quintile, and less than half a serving per day on average for the lowest quintile.

Individuals who consumed the most red meat overall had a 62% higher risk of diabetes compared with those who consumed the least (95% CI, 1.53-1.71; P < .001). Further, processed and unprocessed red meat intake in the highest quintile was associated with a 51% (95% CI, 1.44-1.58) and 40% (95% CI, 1.33-1.47) increased risk of developing diabetes, respectively, compared with the lowest quintile (P < .001). According to the authors, these associations were sustained after statistically accounting for body mass index, which could be a mediating variable in this study.

Continuous analysis further revealed that every 1 serving per day increment of red meat was linked to a higher risk of T2D. An additional serving per day was linked to a 28% higher risk of T2D for total red meat, 46% for processed red meat, and 24% for unprocessed red meat.

While high red meat consumption has been linked to increased risk of diabetes in several prior studies, the authors said the associations in the current study were even stronger.

“Possible explanations for the difference are that in most studies, diet was assessed only at baseline, which would not capture dietary change and cumulative effects of red meats on T2D development,” they said. “Our latency analysis supported the hypothesis that red meat’s association with diabetes risk is strongest within 10 to 15 y before T2D diagnosis. Therefore, diabetes risk more than this time after dietary assessment, such as the baseline in most prospective cohorts with long follow-up, will likely be less strongly associated with intake of red meat.”

Additionally, these findings further support dietary recommendations for limiting red meat consumption and finding alternative protein sources to mitigate T2D risk, according to the authors. While an extra serving of red meat was linked to an even higher T2D risk, replacing a serving lowered the risk. Substituting 1 serving of total, processed, and unprocessed red meat per day with a serving of nuts and legumes was associated with a 30%, 41%, and 29% lower risk of diabetes, respectively. Risk was also reduced by 22% when substituting a serving of total red meat per day with a dairy product.

Importantly, the study authors noted their study population was more than 90% White, which could limit the generalizability of these findings. After combining data from all 3 cohorts, the authors had enough cases to examine the associations between red meat intake and T2D risk, particularly among Black participants, and observed similar associations as White participants. However, they noted somewhat less robust associations among Asian and Hispanic participants, which could be attributed to either limited statistical power or variations in how red meat is consumed by different race or cultures within the United States.

Reference

Würtz AML, Jakobsen MU, Bertoia ML, et al. Replacing the consumption of red meat with other major dietary protein sources and risk of type 2 diabetes mellitus: a prospective cohort study. Am J Clin Nutr. 2021;113(3):612-621. doi:10.1093/ajcn/nqaa284