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Carrageenan is found in many supplements and food products including milk chocolate, milk products, frozen dinner, soups, yogurt and ice cream. Carrageenan is derived from red seaweed and has been linked to cancer, gastrointestinal problems, inflammation and leaky gut.
Health hazards of Carrageenan in Food
A recent review on the harmful effects of carrageenan by Tobacman raised questions about the safety of carrageenan containing foods. Concerns have been focused on the potential for degraded carrageenan formed by acid hydrolysis in the stomach and the possibility that this material could promote cancer of the colon.
Rats fed degraded carrageenan have been shown to develop colorectal tumors. Studies have also suggested that degraded carrageenan has the potential to promote colon cancer in rats.
These findings have led to degraded carrageenan being classified by the International Agency for Research on Cancer (IARC) as 2B, a possible human carcinogen, based on animal study data.
An independent committee of the World Health Organization (WHO) concluded that it was not clear whether people with gastrointestinal disease who absorbed some carrageenan, could cause gastrointestinal or immune system problems. Some people reported that eliminating carrageenan from their diet diminished or eliminated their gastrointestinal discomfort.
Food-grade carrageenan contains small amounts of “degraded” carrageenan, and a bit more probably forms in the acidic conditions of the stomach. The International Agency for Research on Cancer, another unit of the WHO, considers degraded carrageenan to be “possibly carcinogenic in humans.” While any possible cancer risk would be quite small, some people may wish to err on the side of caution and avoid carrageenan.
Some experts have been concerned about the safety of carrageenan for infants, given that the GI tract of the infant is still developing. In 2014, however, the WHO committee reviewed new animal studies and concluded that infant formula made with carrageenan is safe.
Sources:
Tobacman JK. Review of harmful gastrointestinal effects of carrageenan in animal experiments. Environ
Health Perspect 109:983–994 (2001).
Ishioka T, Kuwabara N, Oohashi Y, Wakabayashi K: Induction of colorectal tumors in rats by sulfated poly-
saccharides. CRC Crit Rev Toxicol 17:215–244 (1987).
Corpet DE, Taché S, Préclaire M: Carrageenan given as a jelly, does not initiate, but promotes the growth of aberrant crypt foci in the rat colon. Cancer Lett 114:53–55 (1997).
Taché S, Peiffer G, Millet AS, Corpet DE. Carrageenan gel and aberrant crypt foci in the colon of conventional and human
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1240816/pdf/ehp0110-a0176a.pdf
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