Very few topics in life exude as much emotion as food. And in the real food world, the subject of carrageenan (pronounced “kar-uh–gee-nuh n”) is one that fosters a range of emotions and confusion. We receive questions weekly regarding the safety of carrageenan, and so I will share our opinion regarding this subject, in hopes of clearing some of the confusion.
So, What is Carrageenan?
Carrageenan is a common food additive that is derived from a red seaweed, Chondrus crispus, also known as Irish moss. It is a non-nutritive, indigestible plant polymer. It is used in processed foods and other products to keep ingredients from separating, improve texture and add weight and volume to the product. Carrageenan is used as a thickener and emulsifier in many processed food products, including popular “organic” products. These products include energy and chocolate bars, processed lunch meats, dairy alternatives, such as soy, almond and coconut milk, and many organically labeled dairy products like ice cream, yogurt, cottage cream and whipping cream. Most concerning is the fact that carrageenan is even used in most commercial infant formulas (Please see our article on homemade infant formula.). Carrageenan is also being used in numerous vitamin supplements, so-called nutritional shakes, protein powders and toothpaste.
There are two forms of carrageenan, ungraded and degraded. The major difference between the two forms is thought to be the size of their molecules. Ungraded carrageenan, the form used in food and supplement products, contains larger molecules and is thought by many not to be absorbed easily in the human body, barring other factors. It is this form that is used in food products, toothpaste and supplements. However, according to medical researcher Joanne K. Tobacman, MD, associate professor of clinical medicine at the University of Illinois College of Medicine, the size of the molecule does not prevent it from crossing the intestinal barrier (just like undigested food proteins can cross a leaky intestinal barrier) and that carrageenan does actually get into the bloodstream.1
Degraded carrageenan, also known as poligeenan, has not been approved as a food additive and has been classified as a known carcinogen. To date, most of the animal studies on carrageenan have been done using the degraded form, which has been shown to cause gastrointestinal ulcerations and cancers on test animals. The ungraded carrageenan has been given GRAS (Generally Recognized As Safe) status. As research continues, the FDA appears to be unsure of the GRAS status of ungraded carrageenan. As stated on the FDA’s website, “Recent reports on the oral administration of un-degraded sodium and calcium carrageenan of known quality to pregnant animals reveals fetotoxic effects, with or without frank teratogenic effects, in some species at levels that do not greatly exceed the average daily human rate of intake.” “The Select Committee has weighed the foregoing and concludes that: While no evidence in the available information on un-degraded carrageenan demonstrates a hazard to the public when it is used at levels that are now current and in the manner now practiced, uncertainties exist requiring that additional studies should be conducted.”2
Research in 1971 indicated that carrageenan damages immune cells as well as promotes tumor formation and inflammation.3 Medical researcher Joanne K. Tobacman, MD, associate professor of clinical medicine at the University of Illinois College of Medicine, has published 18 studies to date (and most likely more are to come) exhibiting that carrageenan causes inflammation in the gut, which translates into systemic inflammation throughout the body. Chronic inflammation is a known precursor to diseases such as cancer, Alzheimer’s disease, Parkinson’s disease, cardiovascular disease and Crohn’s disease.
According to Dr. Tobacman, one of the leading researchers in the field of digestive health, carrageenan is used in laboratory settings to induce inflammation in tissues of mice to test the anti-inflammatory properties of new drugs. Mice exposed to low concentrations of carrageenan for 18 days develop profound glucose intolerance and impaired insulin action, both of which can lead to the onset of diabetes. It is Dr. Toabacman’s observation that “degraded carrageenan inevitably arises from higher molecular weight (food grade) carrageenan.” It is understood that heating, mechanical processing, bacterial action and acid digestion (a natural process of the stomach) can all accelerate degradation of food-grade (ungraded) carrageenan.4
Factors to Consider
Variables exist within everyone’s diet. Healthy digestive tracts will produce enough stomach acid (hydrochloric acid and pepsin) to facilitate proper digestion of proteins and minerals in our foods. This same action can accelerate the breakdown of ungraded carrageenan. This is especially true in the stomachs of healthy younger people, who tend to have stronger digestion. The mechanical processing that is part of the refined food industry’s practices (organic or otherwise) can alter the molecular structure of all substances, including carrageenan. And lastly, the effect of interactions of a milieu of bacteria with carrageenan is yet undetermined.
It is worth noting that in the GAPS™(Gut and Psychology Syndrome) Diet, Natasha Campbell-McBride, MD excludes carrageenan. The AutoImmune Paleo Diet follows suit with the recommendation to avoid carrageenan.
We recommend to err on the side of prudent avoidance. Regular daily consumption of products containing carrageenan is risky with too many unknown variable factors. Avoidance of carrageenan requires awareness and label reading. Many companies now add in parentheses “seaweed” in an effort to calm concerns that are rising over the safety of carrageenan as a food additive. Fortunately, The Cornucopia Institute, has made available a shopping guide to avoiding organic foods with carrageenan. It is always our recommendation to stick with real traditionally prepared foods that support healthy, optimal digestion and assimilation. When it comes to carrageenan, stay out of the uncharted waters.
1 J K Todacman. Review of harmful gastrointestinal effects of carrageenan in animal experiments. Environmental Health Perspectives. 2001 Oct; 109(10): 983-994. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1242073/
2 Select Committee on GRAS Substances (SCOGS) Opinion: Carrageenan. http://www.fda.gov/Food/IngredientsPackagingLabeling/GRAS/SCOGS/ucm261246.htm
3 Phillip J. Catanzaro et al. Spectrum and Possible Mechanism of Carrageenan Cytotoxicity. The American Journal of Pathology. 1971 Aug; 64(2): 387-404. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2047576/
4 Weil, MD, Andrew. Is Carrageenan Safe? http://www.drweil.com/diet-nutrition/food-safety/is-carrageenan-safe/