New research published in Nature Communications has raised significant public health questions about the safety of common food preservatives, linking their consumption to increased risks of type 2 diabetes and several forms of cancer. While scientists stress the need for further, deeper investigation, the findings have prompted calls for a reassessment of how these widely used additives are regulated.
The evidence comes from one of the largest analyses to date, utilising dietary and health data from over 100,000 adults in the French NutriNet-Santé cohort (2009–2023). Researchers examined the association between exposure to 17 commonly used preservatives, found in ultra-processed foods like ready meals, snacks, cured meats, and packaged sauces, and disease outcomes. The study found that high consumption of food preservatives was associated with a substantially higher risk (up to around 49%) of developing type 2 diabetes compared with lower intake levels. Specifically, twelve of the 17 additives examined showed positive links with diabetes incidence, including both non-antioxidants (such as potassium sorbate, sodium nitrite, and calcium propionate) and certain antioxidant additives currently classified as Generally Recognised as Safe (GRAS).
Experts caution that these observational results do not prove that preservatives cause diabetes or cancer, as the links may be influenced by residual confounding factors like overall poor diet quality, lifestyle differences, and socioeconomic influences. However, the strength and consistency of the associations across multiple compounds warrant closer scientific scrutiny. The findings also reinforce existing concerns about cancer risks, given that processed meats (bacon, ham, sausages) are already classified as Group 1 carcinogens by the World Health Organisation’s IARC, largely due to the synthetic nitrates used in curing which can form DNA-damaging nitrosamines.
Public health experts emphasise that focusing on single additives can be misleading, as preservatives often serve as one marker of a dietary pattern characterised by frequent intake of ultra-processed foods. These foods are typically high in salt, sugar, and unhealthy fats and have already been linked in prior research to elevated risks of obesity, metabolic syndrome, cardiovascular disease, and various cancers. For instance, a 2025 American College of Cardiology review reinforced associations between high ultra-processed food consumption and increased risks of hypertension, digestive diseases, and type 2 diabetes.
The new studies have ignited debate among regulators and food scientists, with campaigners pushing for stricter oversight and clearer consumer labelling, arguing that the "generally recognised as safe" status for some additives should be reevaluated. For consumers, the findings reinforce long-standing dietary guidance from bodies like the Food Standards Agency and the World Cancer Research Fund, which advocate for prioritising whole, minimally processed foods and limiting intake of ultra-processed items. Simple, practical steps to reduce preservative exposure include checking ingredient lists for preservative codes (e.g., E202, E224, E250), choosing fresh or frozen whole foods over packaged equivalents, and preparing meals at home.
While definitive causal links require further interventional and mechanistic studies, the latest 2026 research provides some of the strongest epidemiological evidence yet associating habitual consumption of certain food additives with higher risks of type 2 diabetes and cancer, underscoring the urgent need for updated dietary guidance and ongoing scientific scrutiny.
