Preservatives and heart risk: what a cohort found
A French cohort linked several common food preservatives with higher rates of hypertension, but cannot show that the additives caused disease.
The 60-second version
In a large French cohort, higher exposure to certain food preservatives tracked with more hypertension, but causation was not shown.
Key points
- The analysis covered 112,395 adults with a median 7.9 years of follow-up.
- Eight individual preservatives were associated with hypertension after multiple-test correction.
- Relative hazard ratios compare groups; they are not an individual's absolute risk.
Verdict. Focus on overall diet and blood-pressure care; do not treat the study as proof that a single ingredient causes disease.
A French observational study associated higher intake of several food preservatives with more new cases of high blood pressure. It does not establish that an additive caused any individual's illness, and it is not a reason to stop taking prescribed treatment or fear a single ingredient.
What the researchers measured
The NutriNet-Santé analysis followed 112,395 volunteers in France. Repeated dietary records, including food brands, were matched with ingredient databases and laboratory measurements to estimate exposure. Participants were followed for a median 7.9 years. The study recorded 5,544 new hypertension cases and 2,450 cardiovascular events.
What the association means
In the adjusted models, higher versus lower consumption of non-antioxidant preservatives was associated with a hypertension hazard ratio of 1.29 (95% confidence interval 1.20–1.39) and a cardiovascular-disease hazard ratio of 1.16 (1.04–1.29). For antioxidant preservatives as a group, the hypertension ratio was 1.22 (1.13–1.31). These are relative comparisons between groups, not a 29% chance of getting hypertension.
Among 17 individual preservatives commonly consumed in this cohort, eight had a statistically significant hypertension association after correction for multiple testing. These include potassium sorbate, potassium metabisulphite, sodium nitrite, ascorbic acid, sodium ascorbate, sodium erythorbate, citric acid and rosemary extracts. A substance's appearance on this list is not proof that ordinary exposure is harmful.
Why causation remains open
People who consume more preservative-containing foods can differ in overall diet, activity and other health factors. Statistical adjustment cannot rule out every confounder, and dietary reporting and changing formulations add uncertainty. The cohort was mostly women in France, which also limits simple extrapolation to other populations.
The useful next step
Treat this as another reason to consider the overall quality of a diet, not as a blacklist of eight ingredients. Favor minimally processed foods when feasible, and discuss blood pressure, dietary changes and personal cardiovascular risk with a clinician.