S. Cohen, N. Ito, A Critical Review of the Toxicological Effects of Carrageen and Processed Eucheuma Seaweed on the Gastrointestinal Tract. Crit. Rev. Tocicol. 32(5): 413-444 (2002)
In this study, scientists review the effects of carrageenan on the gastrointestinal tract and dispel erroneous conclusions that had suggested carrageenan could cause cell proliferation or tumor formation. The study was submitted to and reviewed by the Joint FAO/WHO Expert Committee on Food Additives. The conclusion: carrageenan is not a carcinogen, not a tumor promoter, nor a tumor initiator.