Editorial NexoScience
Turn over a packet of sliced ham and read the small print. Somewhere after the pork and the salt you’ll find a few E-numbers, the codes Europe gives to approved additives. Some keep bacteria out. Others stop fat from going rancid or the pink from turning grey. They are in more than one in five packaged foods and drinks sold worldwide, and almost nobody has asked what they do to the heart over years of eating them.
A large French study now has a first answer to the question of whether preservatives and high blood pressure are linked. Among 112,395 adults followed for a median of almost eight years, the people who ate the most preservatives were about 24% more likely to develop high blood pressure than those who ate the least. A narrower group, the preservatives that work by blocking microbes rather than oxygen, was also tied to a 16% higher risk of cardiovascular disease. That is a link, not proof that preservatives cause high blood pressure, and the authors say so plainly.
The work, with Anaïs Hasenböhler as first author and the NutriNet-Santé research team behind it, was published in the European Heart Journal. NutriNet-Santé is an online cohort that has been recruiting French adults since 2009 and asking them, again and again, exactly what they eat.
Which preservatives were linked to high blood pressure
Eight everyday additives made the shortlist. The participants ate 58 different preservatives between them, but only 17 were common enough (eaten by at least one person in ten) to test one by one. After a statistical correction for testing so many at once, eight of those 17 were tied to more cases of hypertension. They were potassium sorbate (E202), potassium metabisulphite (E224), sodium nitrite (E250), ascorbic acid (E300), sodium ascorbate (E301), sodium erythorbate (E316), citric acid (E330) and rosemary extract (E392). Potassium sorbate showed the strongest link, with heavy consumers about 39% more likely to develop high blood pressure than light ones. Citric acid came next, at about 25%.
Each one has a favourite hiding place. The additives turn up all over the supermarket, but some cluster. In this group, 83.7% of sulphite intake came from alcoholic drinks, mainly wine. Processed meat supplied more than half of the nitrites. Processed fruits and vegetables delivered about half of the ascorbates. So the list of preservatives to avoid, if you wanted one, would read a lot like a list of familiar foods: cured meats, wine, soft drinks, ready meals and fruit in jars or tins.
The heart result was narrower. Only one additive on its own was linked to cardiovascular disease, a category that here covered heart attacks, angina, strokes and mini-strokes. It was ascorbic acid, the chemical name for vitamin C, at about 15% higher risk for the heaviest consumers. The broad group of non-antioxidant preservatives was linked to heart disease too, and about 16% of that link appeared to run through high blood pressure itself. That makes sense. Hypertension is one of the main roads to a heart attack or stroke, which is why the research on salty diets and heart risk in women keeps drawing attention.
How researchers tracked preservatives brand by brand
The food diaries were unusually detailed. Every six months, participants logged everything they ate and drank over three random days, including the brand of each packaged product. Some filled in up to 96 of these 24-hour records. The typical participant completed 18. That brand detail is the whole trick. Two jars of tomato sauce can look identical and contain completely different additives, and older studies simply couldn’t tell them apart.
The team then did the label reading for them. Let me explain how. The researchers matched each logged product against three food composition databases, using the version of the recipe on sale on the day it was eaten, since companies reformulate products all the time. For the doses, they ran laboratory tests on real foods and used figures from the European Food Safety Authority (EFSA). Think of it as a receipt for every bite, itemised down to the additive and the milligram, kept for years.
The obvious objection got tested. People who eat lots of preservatives also tend to eat more processed food, and processed food has its own problems. In this group, the heaviest preservative consumers were younger, drank less alcohol and ate more ultra-processed food. So the models were adjusted for fruits and vegetables, red and processed meat, ultra-processed food, salt, sugar, fibre, smoking, weight, exercise and family history, among other factors. The links held. “This limits the likelihood that the observed associations are solely driven by the foods themselves,” the authors wrote. They also ran a check with an outcome that preservatives shouldn’t affect, hip fractures, and found nothing there, which is what you’d hope to see if the method isn’t simply flagging unhealthy lifestyles.
Why vitamin C on a label isn’t the same as in an orange
The vitamin C result is the strangest part. Eating fruit and vegetables rich in vitamin C is consistently tied to healthier hearts. Yet here, the same molecule added to food as a preservative pointed the other way. The authors note that additive ascorbic acid is chemically identical to the natural version. What differs is everything around it: the food it sits in, the dose and how it interacts with other ingredients. Earlier trials of vitamin C and vitamin E supplements also found little or no protection against heart disease, so the idea that “vitamin C is always good for you” was already shakier than it sounds.
Lab work offers some possible reasons. Potassium sorbate is technically a trans fatty acid, and trans fats have a long record of raising blood pressure. In an earlier mouse study with human gut microbes, sorbate combined with fructose over 11 weeks pushed the animals toward fatty liver disease. Cell studies have flagged potential toxicity for sorbate, sodium nitrite, sodium ascorbate and sodium erythorbate. Nitrites can promote oxidative damage. None of this has been shown in people, and the authors treat it as a list of leads, not explanations.
What the study can’t prove about preservatives and health
An association is not a verdict. This is an observational study, so it can show that two things travel together but not that one causes the other, and the authors acknowledge that residual confounding can’t be fully ruled out. They did estimate how strong a hidden factor would need to be to erase the links, and for almost every result it would have to be fairly powerful. The participants were also not typical of France. Nearly 79% were women, they were more educated and had healthier habits than average, and only about 5% developed hypertension, compared with roughly 30% of French adults. Some undiagnosed cases were surely missed. And intakes were mostly modest: no one exceeded the official safe daily limit for sorbates or nitrates, and only a handful of people went over the limits for sulphites or nitrites.
Nobody needs to empty the pantry. The authors stress that their findings don’t overturn standard dietary advice, which already says to eat plenty of fruit, vegetables, legumes and fibre and to limit processed meat and salt. What they add is a second layer: choose fresh or minimally processed versions of those foods when you can, as French health guidance already recommends. They also call for other cohorts to repeat the analysis and for experiments to test the mechanisms. With consumers “exposed to these compounds via thousands of foods and drinks,” as the researchers put it, they argue regulators such as EFSA should re-weigh the benefits of longer shelf life against these possible costs.
Source: Hasenböhler, A., Javaux, G., Payen de la Garanderie, M., Szabo de Edelenyi, F., Yvroud, P., Agaësse, C., et al. “Preservative food additives, hypertension, and cardiovascular diseases: the NutriNet-Santé study.” European Heart Journal (2026). DOI: 10.1093/eurheartj/ehag308
This article summarizes published scientific research for general information. It is not medical advice and does not replace consultation with a qualified health professional.
