Carrageenan (E407)

What is Carrageenan?

Carrageenan is a natural carbohydrate extracted from certain species of red seaweed, traditionally Irish moss (Chondrus crispus) and today mostly Eucheuma seaweeds farmed in Southeast Asia. Irish moss has long been used to thicken traditional puddings. In the EU a less refined form, processed Eucheuma seaweed, has its own code: E407a.

It is important not to confuse it with degraded carrageenan (poligeenan), which is made by treating carrageenan with strong acid at high temperature. Poligeenan has a much smaller molecule, is classified by IARC as possibly carcinogenic, and is not permitted in food.

Why is Carrageenan used in food?

Carrageenan keeps foods smooth and stable. It stops cocoa from settling in chocolate milk, keeps plant-based milks from separating, gives ice cream and dairy desserts a creamy texture, and helps deli meats hold moisture. It works at very low doses and is plant-based, which makes it popular in vegan products.

Is Carrageenan safe? What the research says

What regulators say. The FDA permits carrageenan as an emulsifier, stabilizer and thickener. EFSA re-evaluated it in 2018 and set a temporary acceptable daily intake of 75 mg/kg of body weight. It is temporary not because harm was found, but because EFSA said the data on chemistry, exposure and toxicity had gaps that needed to be filled within five years.

The inflammation question. Concerns come mainly from laboratory and animal studies suggesting carrageenan may trigger inflammation in the gut. Evidence in people is thin: a small pilot trial in patients with ulcerative colitis (Bhattacharyya et al., 2017) reported more relapses in those given carrageenan, but it included very few participants and has been criticized for its design. Much of the alarm online also mixes up food-grade carrageenan with degraded carrageenan.

The organic debate. In 2016 the USDA's National Organic Standards Board voted to remove carrageenan from the list of substances allowed in organic foods, mainly because it believed organic alternatives existed. In 2018 the USDA kept it on the list, noting that regulators had repeatedly found it safe and that substitutes did not do the same job.

Bottom line: at normal intakes carrageenan is considered safe for the general population. People with inflammatory bowel disease who suspect it affects them may reasonably avoid it and discuss this with their doctor.

Carrageenan regulation: US vs EU

Carrageenan is permitted in the US, the EU, Canada, Australia and most other markets. In the US it must be listed by name as "carrageenan." Degraded carrageenan (poligeenan) is not an approved food ingredient anywhere.

Who should limit or avoid Carrageenan?

• People with inflammatory bowel disease (ulcerative colitis, Crohn's disease) who notice symptoms — the evidence is limited, but avoiding it is low-cost. Talk to your gastroenterologist.
• People with a sensitive gut who want to test whether it makes a difference.
• Carrageenan is vegan and gluten-free.