Higher intake of some food preservatives is linked with increased risks of type 2 diabetes and cancer, two studies suggest.
The findings were based on diet and health data from more than 100,000 French adults in the NutriNet-Santé study between 2009 and 2023.
Of 17 preservatives analysed individually, higher consumption of 12 was associated with an increased risk of type 2 diabetes.
Higher intake overall was linked to a 47 per cent increase in incidence.
In the cancer research, several preservatives were linked to higher risk. Potassium sorbate was associated with a 14 per cent higher risk of overall cancer and a 26 per cent higher risk of breast cancer, while sodium nitrite was linked to a 32 per cent higher risk of prostate cancer.
Overall preservative intake was not linked to cancer incidence in the cohort.
Researchers said several compounds could alter immune and inflammatory pathways, possibly triggering cancer development.
Both were observational studies, so they show association rather than cause.
Mathilde Touvier, a coordinator of the diabetes study, said: “This is the first study in the world on the links between preservative additives and the incidence of type 2 diabetes.
“Although the results need to be confirmed, they are consistent with experimental data suggesting the harmful effects of several of these compounds.”
Prof William Gallagher, of University College Dublin, who was not involved with the research, said: “These higher rates of cancer are modest but are significant when taken at a population-based level in terms of potential impact.”
The researchers called on manufacturers to limit unnecessary preservatives and backed advice for consumers to eat fresh, minimally processed foods.