Higher Type 2 Diabetes Risk Went With Diets Heavier in Ultra-Processed Foods

CATEGORY: METABOLIC & BLOOD SUGAR

Every 10% of a person’s daily food intake that came from ultra-processed foods was linked to a 17% higher risk of developing type 2 diabetes over about 11 years, in a study of nearly 312,000 European adults published in The Lancet Regional Health–Europe.¹ Swapping that same 10% for less-processed foods was linked to a 14% to 18% lower risk—and the study found that not all ultra-processed foods carried the same risk.

The Nova System Sorts Foods by Industrial Processing

Researchers sorted foods using the Nova system, which groups foods by how much industrial processing they have been through rather than by their nutrients. At one end are unprocessed or minimally processed foods (fresh or frozen produce, plain meat, eggs, milk, grains) and basic cooking ingredients. In the middle are processed foods—cheese, canned vegetables, cured meats, simple breads—made by adding salt, sugar or oil to whole foods. At the far end are ultra-processed foods: industrial products built from refined ingredients and additives you would not find in a home kitchen, such as packaged snacks, sweetened drinks, ready meals and reconstituted meat products.¹

311,892 Adults, 14,236 Diabetes Cases Over 10.9 Years

The EPIC study enrolled adults across eight European countries in the 1990s, each completing a detailed diet questionnaire at the start. Researchers assigned every food reported to a Nova group and calculated what share of each person’s daily intake, by weight, came from each. Participants were followed for an average of 10.9 years, and new cases of type 2 diabetes were confirmed through several sources, including medical records and registries, rather than self-report alone. Among the 311,892 people analyzed, 14,236 developed the disease.¹

Roughly Half the Link Ran Through Body Fat

After adjusting for age, sex, education, smoking, physical activity and other factors, each 10% higher share of ultra-processed food was linked to a 17% higher risk of type 2 diabetes. The reverse also held: each 10% higher share of minimally processed food was linked to a 6% lower risk, and of processed food to an 8% lower risk. In a modeling exercise that swapped one group for another, replacing 10% of ultra-processed food with minimally processed food was linked to a 14% lower risk, and with processed food to an 18% lower risk. Roughly half of the ultra-processed-food link appeared to run through higher body fat.¹

Savory Snacks and Sweetened Drinks Carried the Risk

When the researchers broke ultra-processed foods into sub-groups, the higher risk was concentrated in savory snacks, processed animal products such as reconstituted meats, ready-to-eat meals, and sugar-sweetened and artificially sweetened drinks. By contrast, ultra-processed breads, biscuits and breakfast cereals, sweets and desserts, and plant-based meat alternatives were linked to a somewhat lower risk. The authors suggest the specific products, rather than the category as a whole, may matter most.¹ Because this was an observational study, it shows an association, not proof of cause: diet was measured once, and people who eat more ultra-processed food may differ in ways the study could not fully capture.

Another Pooling Put the Increase Nearer 12%

Other research points the same way overall: a 2024 review of the pooled evidence graded the ultra-processed food link to type 2 diabetes as convincing.² A separate pooling of prospective studies put the increase nearer 12% for each 10% of intake, and in its three large U.S. cohorts the product pattern differed—savory snacks and refined breads were linked there to lower risk, not higher.³

Key Takeaways

• In 311,892 European adults followed for about 11 years, each 10% of daily food intake from ultra-processed foods was linked to a 17% higher risk of type 2 diabetes.
• Replacing that 10% with minimally processed or processed foods was linked to a 14% to 18% lower risk, in a modeled swap.
• The added risk was driven mainly by savory snacks, processed meats, ready meals and sweetened drinks; some ultra-processed foods, such as breads and cereals, were not linked to higher risk.
• The study is observational and shows an association, not cause and effect.

References

1. Dicken SJ, Dahm CC, Ibsen DB, et al. Food consumption by degree of food processing and risk of type 2 diabetes mellitus: a prospective cohort analysis of the European Prospective Investigation into Cancer and Nutrition (EPIC). Lancet Reg Health Eur. 2024;46:101043. link
2. Lane MM, Gamage E, Du S, et al. Ultra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analyses. BMJ. 2024;384:e077310. link.
3. Chen Z, Khandpur N, Desjardins C, et al. Ultra-processed food consumption and risk of type 2 diabetes: three large prospective U.S. cohort studies. Diabetes Care. 2023;46(7):1335–1344. link.