Carrageenan, degraded carrageenan and poligeenan chemistry and animal safety studies
What it found
Carrageenan is a different substance from degraded carrageenan and poligeenan, which are made by breaking it down with acid.
Animal studies found no cancer or tumour activity from carrageenan taken by mouth.
What they found
Animal and lab studies
Cannot break down inside you
Your body cannot turn carrageenan into poligeenan after you eat it. The authors say worries about eating carrageenan in food are therefore unfounded.
Studies in people and animals
No cancer in animals
Animal studies where carrageenan was given by mouth showed no cancer or tumour growth. The authors say current work supports a lack of cancer activity in people.
Other findings
Different substances entirely
Carrageenan is not the same as degraded carrageenan or poligeenan. Poligeenan and degraded carrageenan are made on purpose by breaking carrageenan down with acid. Early studies confused them by using the wrong names.
What the authors conclude
- They explain that carrageenan, degraded carrageenan and poligeenan are chemically distinct substances made in different ways.
- They state that the body cannot convert carrageenan into poligeenan after eating it.
- They conclude that concerns about carrageenan as a food additive are unfounded because animal studies show no cancer or tumour activity.
How it was done
Food makers have used carrageenan for decades to thicken and stabilise foods. Older studies mixed up the names for carrageenan and its broken-down forms, spreading incorrect information about its use in food.
The authors looked at the chemistry, how each substance is made, and how they react with proteins. They also examined animal studies where these substances were given by mouth. The abstract does not say how many animals were studied or for how long.
What it can’t tell you
- We summarised it from the abstract only.
- This summary relies on animal studies and chemistry reviews. Those cannot prove exactly what happens when people eat carrageenan over many years.
- A review gathers existing research rather than running new tests, so it depends on the quality of earlier work.
The paper
- Title
- Clarifying the confusion between poligeenan, degraded carrageenan, and carrageenan: A review of the chemistry, nomenclature, and in vivo toxicology by the oral route
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Studies in people · animals · lab
- Summarised from
- Abstract only
- Cite
- McKim JM, Willoughby JA, Blakemore WR, Weiner ML (2019). Clarifying the confusion between poligeenan, degraded carrageenan, and carrageenan: A review of the chemistry, nomenclature, and in vivo toxicology by the oral route. Critical reviews in food science and nutrition. doi:10.1080/10408398.2018.1481822PubMed 29902080DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error