Rosemary, Rosmarinus officinalis, the plant that rosemary extract (E392) comes from, in flower in Vieussan, France.
Christian FerrerCC BY 4.0
Illustrative. The plant itself, not the extract used in food, and not a product or a participant from the study.
Vitamin C, Citric Acid and Rosemary Extract Are on a List of Preservatives Tied to Higher Blood Pressure
A common clean label move is to swap preservatives that sound like chemistry for ones that sound like food: vitamin C, citric acid, rosemary. This study puts those exact ingredients on the same list as sodium nitrite. One note before anything else, because it changes how you should read it: this is not a new study. A press release about it was recirculated on September 20, 2026, which is how it landed in front of me, so I went back to the paper itself, which came out in May. I am writing it as an explainer.
- A study that followed 112,395 French adults for a median of 7.9 years found that people with the highest preservative intake had higher rates of high blood pressure than people with the lowest. The paper is not new. It appeared in the European Heart Journal on May 20, 2026, so this is an explainer, not breaking news.
- Of the 17 most eaten preservatives, eight were linked to higher hypertension risk. Four of the eight are the ones clean label products lean on: ascorbic acid (E300), sodium ascorbate (E301), citric acid (E330) and rosemary extract (E392).
- It is observational. The people eating the most preservatives are also eating the most processed food, and the volunteers were 78.7% women, so it cannot show that any additive caused anything.
- It is about preservatives added to processed food, not about vitamin C supplements. Nothing here says to stop taking vitamin C.
- 112,395
- French adults followed
- 7.9
- Years of follow up, median
- 17
- Preservatives analysed one at a time
- 8
- Linked to higher hypertension risk
What the researchers did
The paper comes from the NutriNet Santé cohort in France. The team followed 112,395 adults for a median of 7.9 years, using unusually detailed records of what people ate. They grouped preservatives into two families. Antimicrobial preservatives are the ones that stop bacteria and mold. Antioxidant preservatives are the ones that stop fats from going rancid.
Comparing the highest intake with the lowest, the antimicrobial group was associated with 29% higher rates of hypertension and 16% higher rates of cardiovascular disease, meaning heart attack, stroke and angina. The antioxidant group was associated with 22% higher rates of hypertension. Exposure was close to universal: 99.5% of participants ate at least one preservative in their first two years in the study.
The eight that stood out
The researchers also looked at the 17 most eaten preservatives one at a time. Eight of them were associated with higher hypertension risk.
Four of them are the names you would expect to see on a warning list. E202, potassium sorbate, is a mold inhibitor in baked goods, cheese, dried fruit and wine. E224, potassium metabisulphite, is a sulfite found in wine and dried fruit. E250, sodium nitrite, is the cured meat preservative most people already know about. E316, sodium erythorbate, is a vitamin C relative used in cured meats.
The other four are the surprise. E300, ascorbic acid, is vitamin C used as an antioxidant. E301, sodium ascorbate, is buffered vitamin C. E330, citric acid, turns up in drinks and snacks and is often described as coming from citrus. E392, rosemary extract, is sold as a natural preservative.
Ascorbic acid, E300, was the only one of the eight that was also independently associated with cardiovascular disease. E numbers are the European labelling codes. On a US label you will see the ingredient names instead.
Why the clean label ones matter
Those four, ascorbic acid, sodium ascorbate, citric acid and rosemary extract, are the ingredients a clean label product tends to reach for. Rosemary extract in particular is marketed as the natural alternative to a synthetic preservative, which makes its appearance here the most quotable detail in the paper and also the easiest to over read. All it tells you is that a natural sounding label is not a safety claim in either direction.
The authors point to oxidative stress and effects on pancreatic function as possible mechanisms, and a follow up programme is looking at inflammation, the blood metabolic profile and the gut microbiota. Those are ideas being tested, not findings.
Ingredients that sound like food are still additives
Vitamin C on a label is not vitamin C in a supplement
This is the distinction I would not want you to lose. The study is about ascorbic acid added to processed food as a preservative, eaten alongside many other additives. It did not test vitamin C supplements, and nothing in it says to stop taking one. Those are different exposures asking different questions.
Honest caveat
This is an observational study and cannot show cause. Eating the most preservatives is also a stand in for eating a lot of industrially processed food in general. The authors adjusted for known cardiovascular risk factors, but leftover confounding from overall diet quality is the obvious alternative explanation, and they say so. The cohort is a volunteer French sample that is 78.7% women with a mean age of 42.8, and health conscious volunteers are not the general population, so the findings may not carry over to a US food supply with a different additive profile. The percentages are relative increases on an outcome that is common in absolute terms. No independent cohort has replicated this yet. The American College of Cardiology scan and the earlier conference abstract corroborate the analysis, but they describe the same dataset and the same authors, so they are not independent confirmation.
What this means for you
Nothing here is a reason to avoid citric acid on a label or to clear out your pantry. It is a reason to be a little more sceptical of the clean label halo. Ingredients that sound like food are still additives, and this study cannot separate any single one of them from the pattern of eating a lot of processed food. My read is that the length of an ingredient list tells you more than whether each item sounds natural.
If you have high blood pressure or take medication for it, please do not change anything on the strength of one observational paper. Talk to your doctor or pharmacist. This is general information, not medical advice.
Primary sources
- Hasenböhler A, Javaux G, Payen de la Garanderie M, et al. Preservative food additives, hypertension, and cardiovascular diseases: the NutriNet Santé study. European Heart Journal, published May 20, 2026. Peer reviewed prospective cohort study.
- The same paper, advance article with full text and PDF. Oxford Academic, European Heart Journal, 2026.
- NutriNet Santé journal scan. American College of Cardiology, Latest in Cardiology, May 26, 2026. Independent editorial assessment of the same analysis.
- European Society of Cardiology press release, as republished by ScienceDaily on September 20, 2026. An interested party, used here only for the named additive list.
- Conference abstract of the earlier analysis. European Journal of Public Health, volume 35, supplement 4, 2025.
Common questions
Is this a new study?
No. The paper was published in the European Heart Journal on May 20, 2026, and the American College of Cardiology covered it in a journal scan on May 26. A press release about it was recirculated on September 20, which is how it reached me. I am writing it up as an explainer of existing research, not as new findings.
Should I stop taking vitamin C because ascorbic acid is on the list?
This study did not look at vitamin C supplements, so it gives no reason to stop one. It measured preservatives added to processed food, eaten alongside many other additives. That is a different exposure from a capsule or a powder, and it is a different question. If you have a concern about your own blood pressure or your supplements, that is a conversation for your doctor or pharmacist.
Does this prove that rosemary extract or citric acid raises blood pressure?
No. It is an observational study, so it can show that higher intake tracked with higher rates of hypertension, but it cannot show that any additive caused it. People who eat the most preservatives also tend to eat the most processed food overall, and the authors say that diet quality is the obvious alternative explanation. The mechanisms they suggest, oxidative stress and effects on pancreatic function, are hypotheses that still need testing, and no independent cohort has replicated the result yet.
Stay Curious.
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