PARIS — New research suggests a potential link between the consumption of certain common food preservatives and an increased risk of both cancer and type 2 diabetes. Two large studies, published in The BMJ and Nature Communications, have identified several additives used to extend shelf life and maintain food safety that may have adverse health effects when consumed regularly. These findings are prompting calls for a reassessment of food additive regulations.
The studies, conducted by researchers leveraging data from the French NutriNet-Santé study involving over 170,000 participants, tracked dietary habits alongside long-term health outcomes. The research compared individuals with high intake of foods containing preservatives to those with minimal exposure, controlling for numerous lifestyle factors.
Potential Cancer Risks Linked to Food Preservatives
Analysis of the cancer data, following participants for up to 14 years, focused initially on 58 different preservatives. Researchers narrowed their investigation to 17 commonly consumed additives, finding that six were associated with a higher cancer risk. These included sodium nitrite, potassium nitrate, sorbates, potassium metabisulfite, acetates, and acetic acid – all currently classified as “generally recognized as safe” (GRAS) by the U.S. Food and Drug Administration.
Specifically, sodium nitrite, frequently found in processed meats like bacon and ham, was linked to a 32% increase in prostate cancer risk. Potassium nitrate showed associations with a 22% higher risk of breast cancer and a 13% increase in all cancers studied. Sorbates, used in wine, baked goods, and cheeses to prevent mold, were also implicated, with potassium sorbate linked to a 26% higher risk for breast cancer and 14% increased risk for all cancers.
The study also examined the impact of antioxidants used as preservatives, such as Vitamin C and rosemary extract. While whole food sources of these antioxidants are generally considered healthy, the results indicated that isolating these compounds as additives may have different, and potentially harmful, effects due to how they are processed by the gut microbiome.
Type 2 Diabetes Connection
A parallel study investigating type 2 diabetes revealed similar concerns. Examining data from nearly 109,000 NutriNet-Santé participants, researchers found that twelve of the seventeen studied food additives were connected to a nearly 50% higher risk of developing the condition in those with the highest consumption levels.
Five of the preservatives linked to increased cancer risk – potassium sorbate, potassium metabisulfite, sodium nitrite, acetic acid, and sodium acetate – also appeared to elevate the risk of type 2 diabetes. Additionally, calcium propionate, commonly used to prevent mold in baked goods, was identified as a potential risk factor.
Interestingly, certain antioxidant additives like alpha-tocopherol (Vitamin E), sodium ascorbate (Vitamin C), and rosemary extracts were also associated with increased risk of developing type 2 diabetes. Other additives like phosphoric acid and citric acid, often found in sodas and processed foods, showed similar connections.
Researchers emphasized the observational nature of the studies, acknowledging the potential for confounding variables. However, they noted the studies rigorously adjusted for factors such as physical activity, tobacco and alcohol use, and medication to isolate the impact of the preservatives. Furthermore, analysis of existing research on the same chemicals in animal and cellular models also supports the findings related to oxidative stress and inflammation.
Experts not involved in the studies, such as Dr. David Katz, have echoed the importance of these findings, suggesting they reinforce the benefits of prioritizing fresh, whole foods in the diet. This kind of research encourages a focus on minimally processed foods, particularly plant-based ones.
Given the preliminary nature of these findings, further research is crucial to confirm the observed associations and explore the underlying mechanisms. Anaïs Hasenböhler, first author of both studies, stated that these findings contribute to a growing body of evidence suggesting a need to re-evaluate the regulations governing food ingredients. The team anticipates continued investigation into these specific compounds and their impact on human health, with potential policy changes considered as more conclusive data emerges.
The focus will likely remain on understanding the role of the gut microbiome and the differences in how processed compared to whole foods affect health outcomes.
