What is it?
Carrageenan is a long chain of sugars taken from red seaweed and used to thicken and set foods. The seaweed is treated with an alkali during processing, which keeps the chains long.
E-numbers / Thickeners & emulsifiers / E407
Carrageenan
also: Irish moss extract · Carrageenans · Carrageenin
A seaweed extract that thickens plant milks, cream and desserts. It inflames the gut in animal studies, and large French studies link it to breast cancer and type 2 diabetes.
Scan a barcode to check a food for carrageenan. NutraSafe Pro · £6.99/month · iPhone and Android
Greek Style Yogurt (Milk) (40%) · Whole Milk · Sugar · Dried Skimmed Milk · Vanilla Extract · Stabiliser: Guar Gum, Locust Bean Gum, Carrageenan.
E407
Carrageenan
If you have ulcerative colitis or Crohn's disease, you may want to limit it.
VeganVegetarian
UK supermarket foods that declare E407: 793 of the 43,325 we checked (1.8%)
Counted by its code or its name in the ingredient list. The count includes every form of E407 (E407a).
Only 9.5% of these labels print “E407”. Most use the name: look for “carrageenan”.
Counted by NutraSafe from UK supermarket ingredient lists, September 2026. How we counted
How common it is in UK food, by aisle
- Ice cream and frozen desserts188 products25% of 762
- Yoghurt, milk and dairy176 products7.7% of 2,273
- Cakes, biscuits and desserts156 products4.2% of 3,715
- Fresh meat, poultry and fish48 products1.0% of 4,835
What carrageenan is, what it does and where you will see it
Why it’s worth knowing. If you have ulcerative colitis or Crohn's disease, you may want to limit it. Labels call it carrageenan or E407.
What does it do?
It thickens, sets and holds foods together. It stops liquids separating and gives a smooth, set texture without adding fat.
Where you will see it
Plant milks, dairy and squirty cream, chocolate milk, ice cream, jellies and desserts, some processed and deli meats, and cottage cheese. Labels call it carrageenan or E407.
What the science says
IARC rates broken-down carrageenan as possibly carcinogenic, on animal evidence
The strongest cancer and ulcer findings come from poligeenan, also called degraded carrageenan. It is made by boiling carrageenan in strong acid for hours, which chops it into much shorter pieces, and it is not added to food. Regulators note that some of the shortest chains in food-grade carrageenan overlap with it.
IARC classes degraded carrageenan (poligeenan) as possibly causing cancer in humans (Group 2B), on animal evidence. Food-grade carrageenan was not classifiable (Group 3).
1983Regulator reviewIARC Monograph
Poligeenan is made by breaking carrageenan down in acid at near-boiling heat and is much shorter than food-grade carrageenan.
2019Lab studyCrit Rev Food Sci Nutr (McKim et al.)
Linked to breast cancer and type 2 diabetes in large French studies
The NutriNet-Santé study asked around 100,000 French adults to record everything they ate, then followed their health for about 7 years. In one analysis, the people who ate the most carrageenan had more breast cancer than those who ate the least. In another, people who ate more carrageenan were more likely to develop type 2 diabetes.
Among 92,000 French adults followed for an average of 6.7 years, higher carrageenan intake was linked to a 28% higher risk of breast cancer compared with lower intake.
2024Observational study in peopleSellem et al., PLOS Medicine, NutriNet-Santé cohort
Among 104,139 French adults followed for an average of 6.8 years, each extra 100mg of carrageenan eaten a day was linked to a 3% higher risk of type 2 diabetes.
2024Observational study in peopleSalame et al., The Lancet Diabetes & Endocrinology, NutriNet-Santé cohort
European reviewers could not confirm the limit and made it temporary
In their 2018 review, European reviewers could not confirm a firm daily limit. They made the existing limit of 75mg per kg of body weight a day temporary because of gaps in the data, and asked for better data within five years. A key gap was that nobody had a proven way to measure the shortest chains in food-grade carrageenan, the part linked to possible harm.
Reviewers judged the shared daily limit of 75mg per kg of body weight for carrageenan (E407) and processed Eucheuma seaweed (E407a) should be temporary, pending better data within five years.
2018Regulator reviewEFSA
Reviewers flagged uncertainties about its chemistry, intake and toxicity, including no proven way to measure the short-chain part and no toxicity data on it.
2018Regulator reviewEFSA
Gut inflammation in animal and cell studies
In rats, mice and rabbits, carrageenan has caused ulcers and inflammation in the bowel that look like inflammatory bowel disease, along with changes to the gut lining, its mucus and its bacteria. One small trial in people with ulcerative colitis hints at an effect.
A review of animal experiments reported that carrageenan caused ulcers and inflammation of the bowel with features like human inflammatory bowel disease.
2001Animal studyEnviron Health Perspect (Tobacman)
Cell and animal evidence suggests carrageenan can damage the gut lining, thin its mucus, change gut bacteria and switch on inflammation.
2017Lab and animal studyNutrients / Front Pediatr review
In a small blinded trial, people with ulcerative colitis in remission ate a carrageenan-free diet. 3 of those given carrageenan capsules relapsed within a year, against none on dummy capsules, but only 12 finished the trial, so the result is preliminary.
2017Randomised trial in peopleNutr Healthy Aging (Bhattacharyya et al.)
Where it stands with the regulators
Approved in the UK and the EU, with a temporary daily limit, and kept out of standard infant formula.
Daily limit. 75mg per kg of body weight a day, made temporary by European reviewers in 2018 because of data gaps.
- Legal basis
- On the Food Standards Agency's approved list for Great Britain, carried over from EU law
- Permitted foods
- Many foods, as a thickener and setting agent · Dairy and plant-based drinks and desserts · Processed and deli meats · Jellies, ice cream and sweets
- Maximum levels
- No set maximum in many foods, with specific limits where they are set. Not allowed in standard infant formula.
- History
- European reviewers looked at E407 and E407a again in 2018, made the daily limit temporary and asked for more data within five years. EU rules keep carrageenan out of standard infant formula.
Who should be careful
People with ulcerative colitis, Crohn's disease or a sensitive gut may choose to limit it. Look for carrageenan or E407 on the label.
The honest read
Poligeenan, or degraded carrageenan, carries the cancer and ulcer evidence but is not added to food. European reviewers could not confirm its limit and kept it temporary, animal and cell studies point to gut inflammation, and the large French studies add links with breast cancer and type 2 diabetes. The open questions are real.
Common questions about carrageenan
What is carrageenan?
Carrageenan (E407) is a thickener taken from red seaweed, used to give plant milks, dairy drinks and desserts their texture. It carries a live safety debate: its daily limit has been temporary since European reviewers flagged data gaps in 2018, and animal studies link it to gut inflammation.
What is carrageenan made from?
It is taken from red seaweed, mainly Irish moss (Chondrus crispus) and Kappaphycus. The seaweed is washed, treated with an alkali and filtered, and the carrageenan is dried into a powder.
Is carrageenan bad for you?
It is unresolved. Food-grade carrageenan has caused inflammation in animal and cell studies, a small trial hinted at relapse in ulcerative colitis, and a large French study linked higher intake to breast cancer. European reviewers kept its limit temporary.
Is carrageenan halal and kosher?
It is taken from seaweed, with nothing from animals, so it suits both. Certification depends on the whole production process, so look for a halal or kosher mark on the product if that matters to you.
Does almond milk contain carrageenan?
Some do, some do not. Carrageenan was once common in UK plant milks to stop them separating, but many brands have removed it. The only way to be sure is to check the ingredients for carrageenan or E407.
Is E407 (carrageenan) banned in the UK?
No. Carrageenan is approved in the UK and EU. Its daily limit has been temporary since European reviewers flagged data gaps in 2018, and it is kept out of standard infant formula.
Is carrageenan bad for your gut?
The strongest gut and cancer findings are for degraded carrageenan (poligeenan), which is not added to food. Food-grade carrageenan has caused inflammation in animal and cell studies, and a small human trial hinted at relapse in ulcerative colitis.
What foods contain E407?
Plant milks, dairy drinks and cream, ice cream, jellies and desserts, some processed and deli meats and cottage cheese. Labels call it carrageenan or E407.
Is E407 vegan?
Yes. It comes from red seaweed, with nothing from animals.
Sources
- EFSA: Re-evaluation of carrageenan (E407) and processed Eucheuma seaweed (E407a) as food additives (2018)
- Clarifying the confusion between poligeenan, degraded carrageenan, and carrageenan (Crit Rev Food Sci Nutr, 2019)
- Review of harmful gastrointestinal effects of carrageenan in animal experiments (Tobacman, Environ Health Perspect, 2001)
- A randomized trial of the effects of the no-carrageenan diet on ulcerative colitis disease activity (Bhattacharyya et al., 2017)
- Sellem et al. (2024) Food additive emulsifiers and cancer risk: results from the French prospective NutriNet-Santé cohort, PLOS Medicine
- Salame et al. (2024) Food additive emulsifiers and the risk of type 2 diabetes: analysis of data from the NutriNet-Santé prospective cohort study, The Lancet Diabetes & Endocrinology
Last reviewed: 9 November 2026
It's the only app that does thisUKJaneK
You Need This AppGmac2005
Best AppGK getting skinny UK App Store reviews
See this on every food you scan
NutraSafe reads the label and puts every additive into plain English, with the source, right in the app.
NutraSafe Pro · £6.99/month · iPhone and Android