Common food preservatives linked to higher risk of type 2 diabetes
Foods that rely heavily on preservatives may be doing more than extending shelf life. In a large study spanning more than a decade, people with the highest intake of preservative additives were far more likely to develop type 2 diabetes. The increased risk appeared across many commonly used additives found in everyday processed foods. Researchers say the findings support advice to limit highly processed products when possible.
People who consume higher amounts of food preservatives may face a greater risk of developing type 2 diabetes, according to a large new study. Preservatives are commonly added to processed foods and beverages to extend shelf life. The research was conducted by scientists from Inserm, INRAE, Sorbonne Paris Nord University, Paris Cité University and Cnam as part of the Nutritional Epidemiology Research Team (CRESS-EREN). The findings are based on health and diet data from more than 100,000 adults enrolled in the NutriNet-Santé cohort and were published in the journal Nature Communications.
Preservatives are part of the broader category of food additives and are widely used throughout the global food supply. Their presence is extensive. In 2024, the Open Food Facts World database listed around three and a half million food and beverage products. More than 700,000 of those products contained at least one preservative.
Two Major Types of Preservative Additives
In their analysis, Inserm researchers divided preservative additives into two main groups. The first group includes non-antioxidant preservatives, which slow spoilage by limiting microbial growth or slowing chemical reactions in food. The second group consists of antioxidant additives, which help preserve foods by reducing or controlling exposure to oxygen in packaging.
On ingredient labels, these additives typically appear under European codes between E200 and E299 (for preservatives in the strict sense) and between E300 and E399 (for antioxidant additives).
Why Researchers Are Investigating Preservatives
Earlier experimental research has raised concerns that some preservatives may harm cells or DNA and interfere with normal metabolic processes. However, direct evidence linking preservative intake to type 2 diabetes in large human populations has been limited until now.
To better understand this potential connection, a research team led by Mathilde Touvier, Inserm Research Director, examined long-term exposure to food preservatives and the incidence of type 2 diabetes using detailed data from the NutriNet-Santé study.
Tracking Diet and Health Over More Than a Decade
The study followed more than 100,000 French adults between 2009 and 2023. Participants regularly provided information about their medical history, socio-demographic background, physical activity, lifestyle habits, and overall health.
They also submitted detailed food records covering multiple 24-hour periods. These records included the names and brands of industrial food products they consumed. Researchers cross-referenced this information with several databases (Open Food Facts, Oqali, EFSA) and combined it with measurements of additives in foods and beverages. This allowed the team to estimate each participant's long-term exposure to preservatives.