Some food preservatives used in processed foods may be linked to higher risks of high blood pressure and cardiovascular disease, according to a large French study.
The research, published in the European Heart Journal, followed more than 112,000 adults and found that people who consumed the most preservative additives had higher risks of hypertension and cardiovascular disease than those who consumed the least. The study was observational, so it cannot prove the preservatives caused those conditions. But it adds to growing research on whether specific additives may help explain some of the health risks associated with industrially processed foods.
Food preservatives are used to keep foods safe, slow spoilage and maintain quality during storage and transportation. They can help prevent mold, bacterial growth, browning or rancidity. But researchers are increasingly studying whether some additives may have effects beyond preservation, especially when consumed regularly as part of a highly processed diet.
The study was part of NutriNet-Santé, a long-running French nutrition study. It included 112,395 volunteers who regularly reported what they ate and drank using detailed dietary records. Researchers analyzed the ingredients in those foods and drinks, including preservative additives, then followed participants’ health for an average of seven to eight years.
Nearly all participants, 99.5%, consumed at least one food preservative during the first two years of the study.
Overall, people who consumed the highest amounts of non-antioxidant preservatives had a 29% higher risk of developing hypertension compared with those who consumed the lowest amounts. They also had a 16% higher risk of cardiovascular disease, including heart attack, stroke and angina. Non-antioxidant preservatives are used to limit the growth of microbes such as mold and bacteria.
People who consumed the most antioxidant preservatives had a 22% higher risk of hypertension. Antioxidant preservatives are used to slow chemical changes that can make foods brown, spoil or become rancid.
The researchers also looked at 17 commonly consumed preservatives and found eight that were specifically linked to high blood pressure: potassium sorbate, potassium metabisulfite, sodium nitrite, ascorbic acid, sodium ascorbate, sodium erythorbate, citric acid and rosemary extract. Ascorbic acid was also specifically linked to cardiovascular disease.
That list needs careful interpretation. Some of those names may sound familiar because they can also occur naturally or be associated with nutrients. Ascorbic acid, for example, is vitamin C, and citric acid occurs naturally in citrus fruits. But this study looked at additive exposure from processed foods, not vitamin C from oranges or citric acid from lemons.
“Food preservatives are used in hundreds of thousands of industrially processed foods. Experimental studies suggest that some preservative food additives may be harmful to cardiovascular health, but we have not had enough evidence on the impact of these ingredients in humans,” said Anaïs Hasenböhler, a doctoral student at Université Sorbonne Paris Nord and Université Paris Cité. “As far as we know, this is the first study of its kind to investigate the links between a wide range of preservatives and cardiovascular health.”
The findings do not mean every food with preservatives is harmful or that an occasional packaged food will raise someone’s blood pressure. People who consume more preservative-containing foods may differ in many ways from people who consume fewer, including overall diet quality, sodium intake, lifestyle, income, health habits and access to fresh foods.
The researchers accounted for several factors that can affect cardiovascular risk, but observational studies can never fully rule out the possibility that other differences helped explain the results.
“This study has some limitations inherent to its observational design. However, the findings are based on highly detailed data, and we have taken account of other factors that can increase or lower the risk of cardiovascular disease,” said Dr. Mathilde Touvier, research director at INSERM and senior researcher with the Nutritional Epidemiology Research Team in France.
Touvier said experimental research has suggested some preservatives may contribute to oxidative stress or affect how the pancreas works. The researchers are now studying how food additives and ultraprocessed foods may affect inflammation, oxidative stress, blood markers and the gut microbiome.
The study adds to the broader conversation around ultraprocessed foods, but it also points to a more specific question: whether the ingredient profile of processed foods matters, not only the amount of processing.
That nuance is important. Some processed foods can be useful, affordable or safe options. But the findings support existing advice to build more meals around minimally processed foods when possible, including fruits, vegetables, whole grains, legumes, nuts, seeds, dairy, eggs, fish and other simple ingredients.
“These results suggest we need a re-evaluation of the risks and benefits of these food additives by the authorities in charge, such as the EFSA in Europe and the FDA in the USA, for better consumer protection,” Touvier said. “In the meantime, these findings support existing recommendations to favour non-processed and minimally processed foods, and avoid unnecessary additives.”
The NutriNet-Santé study is supported by several public research and health institutions in France, including the French Ministry of Health, Santé Publique France, INSERM, INRAE, CNAM and University Sorbonne Paris Nord. This project also received support from the European Research Council, the French National Cancer Institute, the French Ministry of Social Affairs and Health, IdEx Université de Paris, the Bettencourt-Schueller Foundation, Sorbonne Paris Nord University and the French Network for Nutrition and Cancer Research. Additional support for one researcher’s laboratory came from European Research Council grants, AFA Crohn RCH France and INSERM’s national Microbiote program.