Citric acid (E330): should you be wary of it?
In short: citric acid (E330) is the molecule that makes lemons sour. The one on food labels is made by a mould, Aspergillus niger, but it is the same molecule, and our own body produces large amounts of it. For the authorities, it is one of the least worrying additives: no intake limit has ever been considered necessary. What changed in 2026: the French NutriNet-Santé cohort linked the highest consumers of added E330 to slightly more type 2 diabetes (+29%) and high blood pressure (+25%). These are associations, not proof: E330 is probably mostly a marker of soft drinks and processed foods. The proven effects lie elsewhere: tooth wear from acidic drinks, and an interaction with aluminium in people with kidney failure. What to do? There is no need to hunt down E330; cutting back on acidic drinks sipped all day long protects both your teeth and your blood sugar.
Updated on 1 November 2026.
It is in almost everything, and its name is reassuring, since it suggests lemons. Yet on social media, E330 is accused of being made from "toxic black mould". And in 2026, two large French studies placed it among the additives associated with diabetes and high blood pressure. Here is what we really know.
This article is part of our series on additives. For the basics (what the "E" means, how an acceptable daily intake is set), read our article on food additives first.
What is citric acid?
Citric acid is a weak organic acid, found naturally in citrus fruits, but also in pineapples, berries, tomatoes and grapes. It gives lemon juice its sharp taste: lemon juice contains about 48 grams per litre, compared with about 9 grams per litre in freshly squeezed orange juice.
Above all, it is a molecule of our own metabolism. Every cell that breathes makes and uses it constantly, in a chain of reactions called the Krebs cycle (or citric acid cycle), which turns sugars and fats into energy. According to the French medicines agency (ANSM), about two kilos of citric acid are formed and broken down this way in our body every day. The citric acid we eat is burned in the same way, without building up; a small part passes into the urine as citrate, which helps prevent certain kidney stones.
In the food industry, it is used as an acidifier (sour taste), an acidity regulator (it stabilises the pH, which helps preservation) and a sequestrant: it "captures" traces of iron or copper that make fats go rancid and cut fruit turn brown. This last role is why the NutriNet-Santé studies discussed below class it among antioxidant preservatives.
It has a small family, grouped together by evaluators as "citrates":
| Number | Name | Typical use |
|---|---|---|
| E330 | Citric acid | Drinks, sweets, jams, canned food |
| E331 | Sodium citrates | Processed cheese, drinks, desserts |
| E332 | Potassium citrates | Drinks, reduced-salt foods |
| E333 | Calcium citrates | Calcium-enriched foods |
Citrates are salts of citric acid and are assessed together with it: "is sodium citrate dangerous?" gets the same answer as for E330, except that sodium citrate also supplies a little sodium.
Where does the citric acid on labels come from?
First isolated from lemon juice in 1784 by the Swedish chemist Carl Wilhelm Scheele, citric acid was extracted from lemons, mostly Italian ones, until the First World War cut off that supply.
In 1917, the American chemist James Currie showed that a common mould, Aspergillus niger, turns sugar into large amounts of citric acid when grown in a very acidic, low-nitrogen medium. Pfizer opened a pilot plant as early as 1919. Belgium played a part in this story: in Tienen (Tirlemont), the company La Citrique Belge, now Citribel, has been making citric acid since 1929 from sugar beet molasses. It is one of Europe's major producers.
Today, almost all food-grade citric acid comes from this fermentation, using selected strains of A. niger: 2.3 million tonnes were produced in 2016, mostly in China, about 70% of it for food and drink.
The process, in brief: the mould is grown in tanks on a sugar syrup (molasses, glucose). It is then removed, and the acid is purified and crystallised: it must be at least 99.5% pure. International specifications require non-toxigenic strains, which do not produce toxins.
Where is it found?
The European regulation on additives (1333/2008) authorises it in a very wide range of food categories, mostly quantum satis, meaning without a set maximum: manufacturers must use the amount needed for the intended effect, and no more. There are a few exceptions, such as a maximum of 3,000 mg per litre in fruit juices and 5,000 mg per litre in nectars. It is also authorised in certain foods for infants and young children.
In practice, you will mostly find it in:
- non-cola soft drinks and lemonades, energy drinks, iced teas, flavoured waters;
- sour sweets and jellies;
- jams, compotes, canned and frozen foods, pre-packed cut fruit and vegetables;
- sauces, flavoured crisps, ready meals;
- outside the plate: effervescent tablets, cosmetics, "descaling" products.
On the label: "acidity regulator: citric acid" or "acid: E330" (in French "acidifiant", in Dutch "citroenzuur").
How much do we eat? In NutriNet-Santé, more than 9 participants out of 10 consumed added E330, about 200 mg a day at the median: the amount in one teaspoon of lemon juice. According to the authors, the additive accounts for only about one sixth of the total citric acid consumed; the rest comes from fruit and juices. Total intake is estimated at about 40 mg per kilo per day in women (OECD, cited by the ANSM), or 2 grams for 50 kg.
What the authorities say: no limit needed
The acceptable daily intake (ADI) is the amount that can be consumed every day, for a lifetime, without appreciable risk. For citric acid, evaluators have never seen the need to set one:
| Year | Body | Conclusion |
|---|---|---|
| 1973 | JECFA (FAO/WHO expert committee) | ADI "not limited" for citric acid and its salts |
| 1990 | EU Scientific Committee for Food | ADI "not specified" |
| 1994 | FDA (United States) | GRAS status ("generally recognised as safe") affirmed |
| 2020 | European Commission | Re-evaluation by EFSA considered "not a high priority" (low concern) |
| 2026 | EFSA | Call for data on levels and use of E330 to E333 (closed on 30 June) |
An ADI "not specified" means that, given the very low toxicity and the amounts consumed, a number would add nothing to consumer protection. In rats, a carcinogenicity study found no adverse effect up to 1,200 mg per kilo per day, or about 84 grams a day for a 70 kg adult. That is hundreds of times more than a high consumer eats.
EFSA has not yet re-evaluated E330. All additives authorised before 2009 must be reassessed; as of 10 September 2026, 70 remained, and citric acid had been put at the back of the queue for lack of any reason for concern. The call for data in March 2026 is a data-gathering step, not an alert.
In Belgium, the consumer organisation Test Achats rates E330 as "acceptable": no known risk to date.
2026: E330 flagged in NutriNet-Santé
Official assessments rely mainly on animal studies. Mathilde Touvier's team (Inserm) has provided human data thanks to NutriNet-Santé, a French cohort of more than 100,000 volunteers who have recorded what they eat, brand included, since 2009. The method is described in detail in our article on potassium sorbate (E202); here is what these studies say about citric acid.
For added citric acid, the researchers compared, over about eight years, the third of participants who consumed the most with the third who consumed the least, taking into account age, sex, smoking, alcohol, physical activity and diet quality, among other factors.
| Study (2026) | Participants | Result for E330 (high vs low consumers) |
|---|---|---|
| Type 2 diabetes (Nature Communications, January) | 108,723 adults, 1,131 cases | +29% (hazard ratio 1.29; confidence interval 1.11-1.51) |
| High blood pressure (European Heart Journal, May) | 112,395 adults, 5,544 cases | +25% (1.25; 1.16-1.34) |
| Cardiovascular disease (same study) | 2,450 cases | No association for E330 |
| Cancer (BMJ, January) | 105,260 adults, 4,226 cases | No association |
The hazard ratio compares how often the disease occurs in two groups: 1.29 means 29% more cases among high consumers, with the factors taken into account held equal. The confidence interval gives the plausible range; if it does not include 1, the result is probably not due to chance.
E330 is one of the 12 preservatives out of 17 associated with diabetes, and one of the 8 out of 17 associated with high blood pressure.
Mathilde Touvier argues that added citric or ascorbic acid is "not exactly natural" and could act differently from the acid in fruit, particularly in the way the gut microbiota handles it. This is a hypothesis. No study has yet tested it for citric acid.
What is proven, and what is not
| Question | What studies show | Level of evidence |
|---|---|---|
| Is E330 toxic or carcinogenic at dietary levels? | No: no effect in rats up to 1,200 mg/kg/day, no association with cancer in humans | Strong |
| Do high consumers have more diabetes and high blood pressure? | Yes, +29% and +25%, in one cohort | Moderate (observational, a single cohort) |
| Is E330 the cause? | Unknown; probably a marker of soft drinks and processed foods | Not demonstrated |
| Does it damage teeth? | Yes, in acidic drinks consumed often | Strong (laboratory and in-mouth studies) |
| Does it increase aluminium absorption? | Yes, at high citrate doses; important in kidney failure | Strong (clinical studies) |
| Does it cause inflammation through mould residues? | Four reported cases, no controlled test | Very weak (case series) |
The real effects: teeth and aluminium
Tooth wear
This is the best-established effect, and lemon juice does the same. Dental erosion is the dissolution of enamel by acids, without bacteria being involved (unlike tooth decay). Citric acid is one of the most erosive acids, for two reasons: it lowers the pH, and it "captures" calcium from the enamel (a chelating effect), which speeds up its dissolution.
In the laboratory, at the same pH, it erodes enamel and dentine more than the phosphoric acid in colas. In volunteers wearing enamel samples in their mouths, adding citric acid to an acidic solution multiplied the loss of enamel surface hardness by 2.5 to 3, and slowed the return of saliva to a neutral pH.
The risk depends mainly on frequency: a lemonade drunk with a meal does far less harm than a bottle sipped all afternoon. "Sugar-free" drinks and sour sweets are affected too: having no sugar does not protect against erosion.
Aluminium and the kidneys
Citrate forms a soluble complex with aluminium that crosses the intestine more easily. In volunteers taking aluminium hydroxide (an antacid), adding calcium citrate sharply increased aluminium absorption. In patients with kidney failure, who eliminate it poorly, this combination caused severe poisoning in the 1980s (bones, brain).
For a healthy person, E330 in food does not pose this problem. But if your kidneys are not working well and you take a medicine containing aluminium, avoid taking it with citrate (soft drinks, citrus juices, effervescent tablets) and talk to your doctor or pharmacist.
"Black mould": the story of the four cases
The most widespread fear comes from an article published in 2018 in Toxicology Reports by Iliana Sweis and Bryan Cressey (Department of Surgery, University of Illinois at Chicago). They describe four patients with joint, muscle, digestive or respiratory pain a few hours after products containing "manufactured" citric acid, but not after eating lemons. Their hypothesis: fragments or residues of Aspergillus niger, a mould known to cause allergies, could trigger inflammation in predisposed people.
Remember that the mould is removed and the acid purified to over 99.5%, and that A. niger is not the "toxic black mould" of damp walls (that nickname refers rather to Stachybotrys): it is a common mould, also used to produce food enzymes, and industrial strains must be non-toxigenic. These patients' symptoms were not necessarily imaginary, but other causes are possible: the acidity itself (reflux), other ingredients, or the nocebo effect (feeling symptoms because you expect them).
True or false?
"The citric acid on labels is natural, since it comes from lemons." False. It is made by fermentation, not extracted from lemons. But the molecule is identical, and our body produces it too.
"The new Levothyrox was toxic because of citric acid." Not demonstrated. In 2017, the new formula of this thyroid medicine, sold in France, contained citric acid, and many patients reported side effects. The French medicines agency (ANSM) calculated that one tablet contained less than one milligram (0.85 mg), about 2,300 times less than the average daily dietary intake, and concluded that these amounts could not cause toxicity.
"Citrates (E331 to E333) are more dangerous." False: they are its salts, assessed together with it.
Who should pay attention?
Nobody needs E330, but nobody is in danger from eating it at dietary levels. A few situations do deserve some attention:
| Your situation | What is reasonable |
|---|---|
| You drink soft drinks, iced teas or sports drinks every day | Cut down, or drink them with meals rather than sipping them: it is good for your teeth, and it cuts sugar (or sweeteners) at the same time |
| Sensitive teeth, erosion diagnosed by your dentist | Limit acidic drinks and sour sweets, drink through a straw, rinse with water afterwards |
| Kidney failure and a medicine containing aluminium | Do not take them with drinks or tablets containing citrate; talk to your doctor |
| Repeated symptoms after products containing E330 | See a doctor rather than self-diagnosing: citric acid itself very rarely causes allergies, and other causes are possible |
| Family history of diabetes or high blood pressure | No hunt for E330: weight, physical activity, salt and sugary drinks weigh far more heavily |
In practice: the habits that really matter
- Acidic drinks with meals, not continuously. This is the most useful habit for your teeth.
- Water first: tap water or plain mineral water contains no E330. "Lemon-flavoured" water often does.
- Sour sweets in moderation: they combine sugar and acidity, and stay in the mouth for a long time.
- No need to hunt for E330 on labels: its presence alone is no reason to put a product back.
- Lemon in cooking is nothing to worry about, but lemon water sipped all day wears teeth down like a soft drink.
To cut sugar in drinks without switching to sweeteners, see also our article "Am I eating too much sugar?" and our review of sweeteners.
What next?
EFSA closed its data collection on citric acid and citrates on 30 June 2026; the re-evaluation will follow, at a date not yet announced, and may take NutriNet-Santé into account. If other cohorts find the same signal for diabetes or high blood pressure, or if experiments identify a mechanism specific to added citric acid, the question will arise again. We will update this article.
Further reading: how can such an ordinary molecule raise questions?
It is paradoxical to see diabetes associated with a molecule that the body makes by the kilo and that citrus fruits contain. Three explanations are possible, and they are not mutually exclusive.
1. E330 is a marker. Added citric acid is found mainly in sweet and processed products; even after adjustment, the group that consumes the most eats somewhat differently. E330's own share would then be small, or even nil.
2. An effect on behaviour. In a soft drink, acidity balances the very sweet taste and makes the drink more pleasant, so people drink more. The authors also put forward general avenues for preservatives (oxidative stress, inflammation, microbiota), without specific evidence for citric acid.
3. An effect specific to the additive, consumed outside the matrix of a fruit. This is Mathilde Touvier's hypothesis; it remains to be tested.
A single cohort, however well designed, cannot decide between these explanations: replications and experiments will be needed.
Sources
ANSM. (2017). [Citric acid and D-mannitol: assessment of the excipients of Levothyrox 150 µg] [Untitled document dated 14 September 2017; in French]. French National Agency for Medicines and Health Products Safety. https://ansm.sante.fr/uploads/2023/11/16/7751ed2213d09387c6dbe72d65682ce0.pdf
Brandão, A. C. S., Bicego-Pereira, E. C., Del Bel Cury, A. A., & Tenuta, L. M. A. (2022). Effect of pH and titratable acidity on enamel and dentine erosion. Clinical Oral Investigations, 26. https://investigadores.anid.cl/en/public_search/work?id=708976
Coburn, J. W., Mischel, M. G., Goodman, W. G., et al. (1991). Calcium citrate markedly enhances aluminum absorption from aluminum hydroxide. American Journal of Kidney Diseases, 17(6), 708-711.
EFSA. (2026, 4 March). Open call for food additives analytical data and use levels in food and beverages intended for human consumption. European Food Safety Authority. https://www.efsa.europa.eu/en/call/open-call-food-additives-analytical-data-and-use-levels-food-and-beverages-intended-human
European Commission. (2020). Commission Regulation (EU) 2020/1419 of 7 October 2020 amending Annex II to Regulation (EC) No 1333/2008 as regards the use of ascorbic acid (E 300) and citric acid (E 330) on white vegetables intended for further processing. Official Journal of the European Union. https://eur-lex.europa.eu/eli/reg/2020/1419/oj
European Commission. (2026). Re-evaluation: state of play of the re-evaluation of safety of permitted food additives by EFSA as of 10 September 2026. https://food.ec.europa.eu/food-safety/food-improvement-agents/additives/re-evaluation_en
European Society of Cardiology. (2026, 21 May). Common food preservatives linked to high blood pressure and heart disease [Press release]. EurekAlert! https://www.eurekalert.org/news-releases/1128635
Hasenböhler, A., Javaux, G., Payen de la Garanderie, M., et al. (2026a). Associations between preservative food additives and type 2 diabetes incidence in the NutriNet-Santé prospective cohort. Nature Communications, 16, 11199. https://doi.org/10.1038/s41467-025-67360-w
Hasenböhler, A., Javaux, G., Payen de la Garanderie, M., et al. (2026b). Intake of food additive preservatives and incidence of cancer: results from the NutriNet-Santé prospective cohort. BMJ, 392, e084917. https://doi.org/10.1136/bmj-2025-084917
Hasenböhler, A., et al. (2026c). Preservative food additives, hypertension, and cardiovascular diseases: the NutriNet-Santé study. European Heart Journal, ehag308. https://doi.org/10.1093/eurheartj/ehag308
Hughes, J. A., et al. (2000). Effects of pH and concentration of citric, malic and lactic acids on enamel, in vitro. Journal of Dentistry, 28(2), 147-152. https://doi.org/10.1016/s0300-5712(99)00060-3
JECFA. (1973). Citric acid (evaluation No. 218, ADI "not limited"). Joint FAO/WHO Expert Committee on Food Additives. https://www.inchem.org/documents/jecfa/jeceval/jec_436.htm
JECFA. (1999). Citric acid: specifications (FNP 52 Add. 7). FAO. https://www.fao.org/docrep/X3860E/X3860E11.htm
Kirschbaum, B., & Schoolwerth, A. C. (1989). Hyperaluminaemia associated with oral citrate and aluminium hydroxide. Human Toxicology, 8, 45-47.
Penniston, K. L., Nakada, S. Y., Holmes, R. P., & Assimos, D. G. (2008). Quantitative assessment of citric acid in lemon juice, lime juice, and commercially-available fruit juice products. Journal of Endourology, 22(3), 567-570. https://doi.org/10.1089/end.2007.0304
Sweis, I. E., & Cressey, B. C. (2018). Potential role of the common food additive manufactured citric acid in eliciting significant inflammatory reactions contributing to serious disease states: a series of four case reports. Toxicology Reports, 5, 808-812. https://doi.org/10.1016/j.toxrep.2018.08.002
Test Achats. (n.d.). E330 - Acide citrique [Food additives comparison tool; in French]. https://www.test-achats.be/sante/alimentation-et-nutrition/securite-alimentaire-et-additifs/comparateur/additifs-alimentaires/details/E330
U.S. Food and Drug Administration. (1994, 12 December). Citric acid and certain citrate derivatives; affirmation of GRAS status as direct human food ingredients. Federal Register, 59(237). https://www.govinfo.gov/content/pkg/FR-1994-12-12/html/94-30496.htm
West, N. X., Hughes, J. A., & Addy, M. (2001). The effect of pH on the erosion of dentine and enamel by dietary acids in vitro. Journal of Oral Rehabilitation, 28(9).