A diet high in whole grains, fruits and vegetables and low in animal products and sugary drinks is more sustainable and linked to a lower risk of type 2 diabetes than a diet that skimps on plant foods and is rich in items such as red meat.

Dr Solomon Sowah and colleagues at the MRC Epidemiology Unit scored the diets of 23,700 participants in the EPIC-Norfolk study to see how well they adhered to the planetary health diet, a plant-heavy regimen that was developed in 2019 to reduce the risk of conditions like type 2 diabetes, while also lowering emission of greenhouse gasses such as methane and CO2.

The scientists tracked how many study participants developed type 2 diabetes over the next 20 years, finding that nearly 3,500 participants developed the disease. Those in the top 20% of diet adherence had a 32% lower incidence of type 2 diabetes than those in the bottom 20%, and their greenhouse gas emissions were estimated to be 18% lower.

The authors conclude that promoting adherence to the planetary health diet in the general population should be considered as part of strategies aimed at the prevention of type 2 diabetes, and for simultaneously reducing the adverse environmental impact linked to food production. However, they acknowledge that their observational findings do not show that lack of adherence to the planetary healthdiet causes type 2 diabetes.

Reference

• Solomon A. Sowah, Fumiaki Imamura, Daniel B. Ibsen, Pablo Monsivais, Nicholas J. Wareham, Nita G. Forouhi. The association of the planetary health diet with type 2 diabetes incidence and greenhouse gas emissions: findings from the EPIC-Norfolk Prospective Cohort Study; PLOS Medicine. 16 October 2025; DOI: 10.1371/journal.pmed.1004633