Red meat molecule linked to higher type 2 diabetes risk in French study

Higher consumption of Neu5Gc, a molecule found mainly in beef and lamb, was associated with a greater risk of type 2 diabetes among 89,953 French adults, although the observational study cannot prove cause and effect.

Researchers analysing data from France’s NutriNet-Santé cohort have linked higher consumption of a sugar molecule found in red meat with a greater chance of developing type 2 diabetes, while stressing that the finding is observational and does not prove the food causes the disease. The study followed 89,953 adults for an average of 7.2 years, during which 966 participants were diagnosed with type 2 diabetes, according to Medical News Today’s summary of the research.

The molecule in question is N-glycolylneuraminic acid, or Neu5Gc. It occurs naturally in most mammals, but human beings no longer make it because of an ancient genetic change. People still consume it mainly through beef and lamb, and in smaller amounts through dairy products. The researchers say Neu5Gc can become incorporated into human tissues, prompting an immune response that may sustain inflammation. That mechanism is still hypothetical and has not been directly confirmed.

In the French cohort, participants were split into five groups based on their estimated Neu5Gc intake from meat. Compared with the lowest consumers, those in the highest intake group had a 63% higher relative risk of type 2 diabetes, while the second-highest group had a 41% higher risk, according to the report summarising the findings. The authors note that these are relative differences, not the proportion of people who became ill.

The association remained after adjustment for age, sex, physical activity, smoking and overall diet quality. Including body-mass index weakened the link, but it still remained statistically significant. That suggests weight may explain part of the relationship, though not all of it.

The new analysis sits alongside a broader body of research that has repeatedly pointed in the same direction. A systematic review and meta-analysis published in the European Journal of Clinical Nutrition found that higher red meat intake was associated with worse risk factors for type 2 diabetes. Separate studies in The American Journal of Clinical Nutrition, JAMA Internal Medicine and a multi-ethnic cohort published through PubMed Central have also reported links between greater red meat consumption and a higher risk of developing the disease.

For now, the practical message is one of caution rather than certainty. The French findings add another possible explanation for why diets heavy in red meat may be associated with poorer metabolic health, but they do not establish that Neu5Gc itself is the cause.