GROWING evidence is raising questions about the metabolic safety of food preservatives, as new prospective data suggest associations with a higher incidence of type 2 diabetes. In a large French cohort, higher cumulative exposure to several widely used preservative additives was linked to increased diabetes risk, even after extensive adjustment for confounders.
Food Preservatives and Diabetes Risk in a National Cohort
The findings come from the NutriNet-Santé study, a long-running prospective cohort that followed 108,723 adults in France between 2009 and 2023. Participants were predominantly women (79.2%), with a mean age of 42.5 years at baseline. Dietary intake was assessed using repeated 24-hour dietary records, allowing detailed estimation of long-term exposure to additives.
Researchers evaluated exposure to 58 food preservatives using multiple food composition databases, complemented by ad-hoc laboratory assays to measure additives directly in food matrices. Associations with incident type 2 diabetes were analysed using multi-adjusted Cox proportional hazards models.
Which Food Preservatives Were Associated with Higher Incidence?
Of the 58 preservatives assessed, 17 were consumed by at least 10% of participants and analysed individually. Thirteen were associated with a higher incidence of type 2 diabetes, with 12 remaining significant after correction for multiple testing. These included potassium sorbate, potassium metabisulfite, sodium nitrite, acetic, citric and phosphoric acids, sodium acetates, calcium propionate, sodium ascorbate, alpha-tocopherol, sodium erythorbate, and rosemary extracts.
Over the follow-up period, 1,131 new cases of type 2 diabetes were identified. The study assessed cumulative exposure, reflecting habitual intake rather than single foods, which is particularly relevant given the widespread use of preservatives in processed and ultra-processed foods.
Making Molecular Signals Clinically Meaningful
While some preservatives, such as nitrites and certain acids, have been experimentally linked to metabolic or inflammatory pathways, the authors emphasise that epidemiological data in this area have been limited. This study does not establish causality but suggests that long-term exposure to specific additives may be relevant to diabetes development.
Reference
Hasenböhler A et al. Associations between preservative food additives and type 2 diabetes incidence in the NutriNet-Santé prospective cohort. Nat Commun. 2026;16(1):11199.
