EuroWire, PARIS: Researchers have reported evidence linking higher intake of certain food preservatives to an increased risk of type 2 diabetes, based on a large observational study tracking dietary habits and health outcomes over more than a decade.
The findings are drawn from the NutriNet-Santé study, an ongoing population-based research project that has followed the diets and health of more than 100,000 adults in France since 2009. Researchers analyzed repeated dietary records provided by participants and compared preservative intake with the incidence of type 2 diabetes diagnosed during the follow-up period, which extended to 2023.
According to the analysis, participants with the highest overall consumption of food preservatives showed a substantially higher rate of developing type 2 diabetes than those with the lowest intake. After adjusting for factors such as age, sex, body mass index, physical activity, smoking status, education level and overall dietary quality, the researchers reported that high preservative exposure was associated with an increase in diabetes incidence approaching 50 percent compared with low exposure.
The study assessed exposure to 17 preservatives that were consumed by at least 10 percent of participants. These substances are widely used in packaged foods to prevent spoilage, inhibit microbial growth and extend shelf life. The analysis identified associations between type 2 diabetes and both non-antioxidant preservatives, such as potassium sorbate, sodium nitrite, acetic acid and calcium propionate, and antioxidant preservatives, including sodium ascorbate, citric acid, phosphoric acid and rosemary extracts.
Researchers also examined preservative intake by category. High consumption of non-antioxidant preservatives was associated with the strongest increase in diabetes risk, while antioxidant preservatives were linked to a lower but still elevated risk. The associations were observed independently of total calorie intake, sugar consumption and other markers of dietary balance, suggesting that the links were not solely explained by broader eating patterns.
The findings were published in the journal Nature Communications. The authors emphasized that the study was observational in design, meaning it identified statistical associations rather than establishing a direct cause-and-effect relationship. However, they noted that the results were consistent with experimental research indicating that some preservatives may influence metabolic processes, including glucose regulation and inflammation.
Dietary records used to assess additive exposure
Type 2 diabetes is a chronic condition affecting hundreds of millions of people worldwide and is associated with serious complications such as cardiovascular disease, kidney failure and vision loss. Global prevalence has risen steadily over recent decades, a trend commonly linked to changes in diet, physical inactivity and increasing consumption of processed foods.
The study adds to a growing body of research examining the health effects of ultra-processed foods, which typically contain multiple additives, including preservatives, colorings and flavor enhancers. Previous population studies have reported higher risks of obesity, cardiovascular disease and diabetes among individuals with greater intake of ultra-processed foods. The current research sought to isolate the role of preservatives themselves rather than overall food processing.
Researchers said dietary exposure was estimated using detailed food composition databases that identify additive content in branded food products. Participants completed multiple 24-hour dietary records during follow-up, allowing investigators to capture changes in consumption over time and reduce the likelihood of measurement error. Cases of type 2 diabetes were identified through self-reports validated by medical records, medication use and biological data where available.
Study design focused on long term consumption patterns
Public health experts note that preservatives are regulated and considered safe within established intake limits, but the study highlights the importance of continued evaluation of long-term health effects, particularly when additives are consumed frequently and in combination. The authors stated that further research, including clinical and mechanistic studies, would be needed to better understand how specific preservatives may influence metabolic health.
While the findings do not call for immediate changes to food safety regulations, they reinforce existing dietary guidance that encourages limiting consumption of highly processed foods and prioritizing fresh or minimally processed alternatives. Researchers said the results could inform future nutritional recommendations and contribute to discussions on food formulation and labeling aimed at reducing the burden of chronic metabolic diseases.