Preservatives in Food Linked to Diabetes and Cancer – Researchers Warn

New comprehensive research indicates that several common preservatives in industrially processed food may increase the risk of both type 2 diabetes and cancer. The findings raise questions about current food regulations—and about what we are actually putting into our bodies on a daily basis.

Preservatives are widely used to extend the shelf life of packaged foods—from bread and cold cuts to ready meals and soft drinks. But two new studies published in the respected medical journals Nature Communications and The BMJ indicate the price for longer shelf life may be high.

The researchers found links between high consumption of several preservatives and an increased risk of both type 2 diabetes and certain types of cancer. Since these additives are found in foods consumed daily by millions of people worldwide, the results are being described as a potential public health concern.

Over 100,000 People Followed for 14 Years

The studies are based on data from more than 100,000 French adults who participated in the long-term diet and health survey NutriNet-Santé between 2009 and 2023. Participants reported in detail what they ate, which was then linked to databases of food additive contents.

In total, 17 different preservatives were analyzed, both as a group and individually.

Cancer: Certain Substances Stand Out

In the cancer study, researchers found no clear association between preservatives as a whole and cancer. However, several individual substances stood out. Those with high consumption of, for example, potassium sorbate had a clearly increased cancer risk, as did those who frequently ingested sulfites.

Nitrites and nitrates—common in processed meats—were also linked to a higher risk of, among others, prostate and breast cancer. Acetic acid and acetates, often used as acidity regulators and preservatives, were also associated with higher cancer risk.

Researchers point out that these substances may affect the immune system and inflammatory processes in the body, which in turn can contribute to cancer development.

Diabetes: Even Stronger Association

The results were even more striking when it came to type 2 diabetes. Higher consumption of preservatives in general could be linked to a sharply elevated risk—up to nearly 50 percent higher compared to those who consumed the least.

Of the 17 analyzed substances, 12 were clearly linked to an increased risk of diabetes. According to the researchers, this is the first study of its kind to show such a broad association between preservatives and incidence of type 2 diabetes.

“Small Increases in Risk – But Major Consequences”

The studies are observational, which means they cannot prove causation. The researchers also do not rule out that other lifestyle factors may play a role. At the same time, they emphasize that the results are robust, based on long-term follow-up, and are consistent with previous laboratory studies showing cell and DNA damage from certain additives.

Independent researcher William Gallagher points out that even moderate increases in risk are serious when they affect large populations.

“On an individual level the effect may seem small, but on a societal level it could mean many extra cancer cases,” he says.

Call to Review Regulations—and Choose Less Processed Food

The researchers are now calling for a reevaluation of current rules on preservatives and urge the food industry to reduce the use of unnecessary additives, especially in ultra-processed foods.

Until then, advice for consumers is clear—and somewhat concerning: choose fresh ingredients, cook more from scratch, and cut down on highly processed foods.

This can be a simple choice at the store—but with far-reaching consequences for your health.