Consumption of preservatives is associated with a higher risk of cancer

Higher consumption of food preservatives, widely used in industrially processed foods and beverages to extend their shelf life, is associated with a slightly lower risk. cancer majoraccording to a study carried out in France and published in The BMJ magazine.

Although its authors specify that more research is needed to better understand these links, they warn that this new data requires the reevaluation of the regulations governing the use of these additives by the food industry to improve consumer protection.

Preservatives are substances added to packaged foods to extend their shelf life. Some experimental studies have shown that certain preservatives can damage cells and DNAbut strong evidence linking them to cancer risk remains scarce.

To address this issue, researchers set out to examine the association between exposure to preservative food additives and cancer risk in adults, using detailed dietary and health data from 2009 to 2023.

Their findings are based on 105,260 participants of 15 years or more (average age 42 years; 79% women) enrolled in the NutriNet-Santé cohort study, who were cancer-free and completed regular, brand-specific 24-hour dietary records over an average period of 7.5 years. Health questionnaires and official medical and death records were then used to trace cancer cases back to December 31, 2023.

A total of 17 individual preservatives, including citric acid, lecithins, total sulfites, ascorbic acid, sodium nitrite, potassium sorbate, sodium erythorbate, sodium ascorbate, potassium metabisulfite, and potassium nitrate.

The preservatives were grouped into not antioxidants (which inhibit microbial growth or slow chemical changes that lead to spoilage) and antioxidants (which delay or prevent food spoilage by eliminating or limiting oxygen levels in the packaging).

During the follow-up period, 4,226 participants received a diagnosis of cancer, including 1,208 breast, 508 prostate, 352 of colorectal cancer and 2,158 of other types of cancer.

Of the 17 individually studied preservatives, 11 were not associated with cancer incidence and no link was found between total preservatives and cancer incidence.

However, higher intake of several preservatives (mostly non-antioxidants, such as potassium sorbate, potassium metabisulfite, sodium nitrite, potassium nitrate, and acetic acid) was associated with an increased risk of cancer compared to non-consumers or consumers to a lesser extent.

For example, total sorbates, specifically potassium sorbate, were associated with increased 14% in overall cancer risk and an increase in 26% in the risk of breast cancer, while total sulfites were associated with an increase in 12% in overall cancer risk.

Sodium nitrite was associated with an increase in 32% in prostate cancer risk, while potassium nitrate was associated with an increased risk of overall cancer (13%) and breast cancer (22%).

Total acetates were associated with an increased risk of overall cancer (15%) and breast cancer (25%), while acetic acid was associated with an increased risk of overall cancer of the 12%.

Among the antioxidant preservativesonly total erythorbates and specific sodium erythorbate were found to be associated with increased cancer incidence.

While more studies are needed to better understand these potential risks, the researchers note that several of these compounds can alter immune and inflammatory pathwayspossibly triggering the development of cancer.

This is an observational study, so no firm conclusions can be drawn about cause and effectand the researchers cannot rule out the possibility that other unmeasured factors may have influenced their results.

However, they say this was a large study based on detailed dietary records linked to food databases during 14 years and the results are consistent with existing experimental data suggesting cancer-related adverse effects of several of these compounds.

“This study provides new knowledge for the future reassessment of the safety of these food additives by health agencies.”considering the balance between benefit and risk for food preservation and cancer,” they conclude.

In the meantime, they call on manufacturers to limit the use of unnecessary preservatives and support recommendations for consumers to prefer freshly made food and minimally processed.

From a political perspective, Preservatives offer clear benefits by extending the shelf life of foods and reducing costswhich may be particularly important for lower-income populations, American researchers note in a linked editorial.

However, they point out that widespread and often insufficiently supervised use of these additives, with uncertainties about their long-term health effects, requires a more balanced approach.

They point out that the findings of NutriNet-Santé may prompt regulatory agencies to review existing policies, such as setting stricter use limits, requiring clearer labeling, and mandating disclosure of additive content, while collaborative global monitoring initiatives, similar to those implemented for trans fatty acids and sodium, could also support evidence-based risk assessments and guide reformulation by the food industry, they write.

“At the individual level, public health guidelines are already more definitive on reducing consumption of processed meat and alcohol, and offer practical measures even as evidence on the carcinogenic effects of preservatives is evolving,” they conclude.