Carrageenan is no longer excluded

Since 2010, the Whole30 elimination phase has specifically called out carrageenan, an additive found in products such as non-dairy creamers and deli meats. If carrageenan was listed as an ingredient, that product was eliminated for the duration of your Whole30. 

In the early days of Whole30, we were of the mindset that if any research or clinical experience (such as that of our medical advisory board) suggested the ingredient was linked to a food sensitivity and/or reaction, we would eliminate that ingredient from the program. Based on the science at the time and the opinions of our medical advisory board, we believed carrageenan posed enough of a health risk (and that enough people could be sensitive to its effect) to recommend leaving it out of the Whole30. 

In my 2012 book It Starts With Food, I summarized our conclusion as follows: “Carrageenan is inflammatory if it gets into the body, which could happen if you have increased gut permeability. (Carrageenan is actually used to create inflammation in lab animals.) Furthermore, in the digestive process, carrageenan may be broken down into components that can cross even a healthy gut barrier.”

Over the years, the Whole30 has evolved in how we think about the program, and how we evaluate science, data, and clinical findings. Today, the goal of the Whole30 is to eliminate as few foods as possible while still delivering participants the best results. This philosophy serves to make the Whole30 more accessible by eliminating fewer foods. It has also encouraged us to lean more heavily on peer-reviewed, high-quality research than clinical experience and anecdotal evidence to determine the program rules.

In 2023 and 2024, we reevaluated the current scientific findings on food-grade carrageenan, inflammation, and health, and found a lack of recent, quality research on this topic. This limitation prevents us from conclusively determining any meaningful impact of carrageenan on the general population. In addition, there has been much confusion around the impact of food-grade carrageenan and other forms of carrageenan—like degraded carrageenan or poligeenan—which is not used in food. (My quote from It Starts With Food about carrageenan being used to create inflammation in lab animals reflects that confusion.) This has led to many misattributing the negative effects of poligeenan in the body to food-grade carrageenan.

Given these factors, today we can safely infer that there is insufficient evidence to justify excluding carrageenan from the program when consumed in recommended amounts as part of a whole foods-based approach—with a few caveats. 

As a result, the Whole30 program rules no longer call out carrageenan as part of Whole30 elimination. 

Here is a summary of that research, our findings, and our conclusions.

Our research standards aim for meta-analyses or systematic reviews. At the very least, a robust body of research would include a greater number of randomized controlled trials (RCTs) in either healthy individuals or a greater array of unhealthy populations to provide a more holistic evaluation. Unfortunately, in the case of food-grade carrageenan, gut health, and inflammation, this body of research does not yet exist.

We did review several mechanistic (in vitro) studies, but they report mixed conclusions on the effects of food-grade carrageenan on human health. These studies don’t carry enough weight to draw a definitive conclusion. This is especially true when considering that experiments performed on isolated cell cultures outside of the human body cannot be reliably extrapolated to indicate health risks for humans. In addition, these studies often administered carrageenan without food, which does not mimic the effect when humans eat carrageenan as part of their diet. 

To complicate this analysis further, there has been significant confusion in the literature between carrageenan and degraded carrageenan (or poligeenan). In early studies, these terms were used interchangeably; however, these are very different substances. Poligeenan cannot be produced biologically; it is only produced via harsh acid hydrolysis in the laboratory. In addition, poligeenan is not approved for use in (nor is it used in) food products. Today, its uses are limited to medical imaging procedures.

Although this nomenclature has been corrected in more recent literature, confusion still exists. This has led some to attribute the effects of poligeenan in the body (which can create increased intestinal permeability, gastric lesions and ulcers, and inflammation) to food-grade carrageenan. As an example, some animal studies (performed with rats and guinea pigs) appeared to implicate carrageenan in the formation of ulcerations and cancerous lesions in the colon. However, the majority of these animal studies used poligeenan, not food-grade carrageenan, in their experiments. 

To be fair, carrageenan itself has produced intestinal damage and increased intestinal permeability in some animal studies. Still, animal studies of food-grade carrageenan also have their flaws. These studies also often delivered carrageenan to rodent subjects without food. Many of the concentrations administered in these studies are comparable to concentrations found in ultra-processed foods, the likes of which you aren’t consuming on the Whole30. In addition, many studies included concentrations much higher than humans would consume as part of a typical diet. Finally, animal studies demonstrate the effects of carrageenan are highly species-dependent. All of these factors make it difficult to extrapolate their results to humans. 

Of note, however: In vitro studies combined with human studies do suggest that carrageenan may be problematic for those with inflammatory bowel diseases (like IBD, ulcerative colitis, or Crohns). This evidence was compelling enough to warrant a special caveat in our recommendations.

There is insufficient evidence to justify eliminating carrageenan as part of the general Whole30 Program Rules. As very few products compatible with the Whole30 contain carrageenan, this rule change doesn’t have a large practical impact on your program. However, uncertainty exists regarding the effects of chronic consumption of food-grade carrageenan for individuals with bowel diseases such as ulcerative colitis, Crohn’s, or IBD. 

As such, if this is your context, you may wish to avoid consuming products with carrageenan during your Whole30 elimination and reintroduction. Read your labels, and avoid non-dairy milks and creamers, non-dairy cheeses, deli meats, and other products that list carrageenan as an additive.

1. McKim JM, Willoughby JA, Blakemore WR, Weiner ML. Clarifying the confusion between poligeenan, degraded carrageenan, and carrageenan: A review of the chemistry, nomenclature, and in vivo toxicology by the oral route. Crit Rev Food Sci Nutr. 2019;59(19):3054–73. DOI: 10.1080/10408398.2018.1481822. PMID: 29902080.
2. Borsani B, De Santis R, Perico V, Penagini F, Pendezza E, Dilillo D, et al. The role of carrageenan in inflammatory bowel diseases and allergic reactions: where do we stand? Nutrients. 2021 Sep 27;13(10). DOI: 10.3390/nu13103402. PMID: 34684400. PMCID: PMC8539934.
3. Liao Y-C, Chang C-C, Nagarajan D, Chen C-Y, Chang J-S. Algae-derived hydrocolloids in foods: applications and health-related issues. Bioengineered. 2021 Dec;12(1):3787–801. DOI: 10.1080/21655979.2021.1946359. PMID: 34281484. PMCID: PMC8806640.
4. Lomartire S, Marques JC, Gonçalves AMM. An overview to the health benefits of seaweeds consumption. Mar Drugs. 2021 Jun 15;19(6). DOI: 10.3390/md19060341. PMID: 34203804. PMCID: PMC8232781.
5. Figueroa JM, Lombardo ME, Dogliotti A, Flynn LP, Giugliano R, Simonelli G, et al. Efficacy of a Nasal Spray Containing Iota-Carrageenan in the Postexposure Prophylaxis of COVID-19 in Hospital Personnel Dedicated to Patients Care with COVID-19 Disease. Int J Gen Med. 2021 Oct 1;14:6277–86. DOI: 10.2147/IJGM.S328486. PMID: 34629893. PMCID: PMC8493111.
6. Lee D, Swan CK, Suskind D, Wahbeh G, Vanamala J, Baldassano RN, et al. Children with Crohn’s Disease Frequently Consume Select Food Additives. Dig Dis Sci. 2018 Oct;63(10):2722–8. DOI: 10.1007/s10620-018-5145-x. PMID: 29862484. PMCID: PMC6290903.
7. Chazelas E, Druesne-Pecollo N, Esseddik Y, de Edelenyi FS, Agaesse C, De Sa A, et al. Exposure to food additive mixtures in 106,000 French adults from the NutriNet-Santé cohort. Sci Rep. 2021 Oct 4;11(1):19680. DOI: 10.1038/s41598-021-98496-6. PMID: 34608173. PMCID: PMC8490357.
8. Feferman L, Bhattacharyya S, Oates E, Haggerty N, Wang T, Varady K, et al. Carrageenan-Free Diet Shows Improved Glucose Tolerance and Insulin Signaling in Prediabetes: A Randomized, Pilot Clinical Trial. J Diabetes Res. 2020 Apr 21;2020:8267980. DOI: 10.1155/2020/8267980. PMID: 32377523. PMCID: PMC7191375.
9. Bhattacharyya S, Shumard T, Xie H, Dodda A, Varady KA, Feferman L, et al. A randomized trial of the effects of the no-carrageenan diet on ulcerative colitis disease activity. Nutr Healthy Aging. 2017 Mar 31;4(2):181–92. DOI: 10.3233/NHA-170023. PMID: 28447072. PMCID: PMC5389019.
10. Naimi S, Viennois E, Gewirtz AT, Chassaing B. Direct impact of commonly used dietary emulsifiers on human gut microbiota. Microbiome. 2021 Mar 22;9(1):66. DOI: 10.1186/s40168-020-00996-6. PMID: 33752754. PMCID: PMC7986288.
11. David S, Wojciechowska A, Portmann R, Shpigelman A, Lesmes U. The impact of food-grade carrageenans and consumer age on the in vitro proteolysis of whey proteins. Food Res Int. 2020 Jan 3;130:108964. DOI: 10.1016/j.foodres.2019.108964. PMID: 32156399.
12. Fahoum L, Moscovici A, David S, Shaoul R, Rozen G, Meyron-Holtz EG, et al. Digestive fate of dietary carrageenan: Evidence of interference with digestive proteolysis and disruption of gut epithelial function. Mol Nutr Food Res. 2017 Mar;61(3). DOI: 10.1002/mnfr.201600545. PMID: 27718308.
13. Jiang H-Y, Wang F, Chen H-M, Yan X-J. κ-carrageenan induces the disruption of intestinal epithelial Caco-2 monolayers by promoting the interaction between intestinal epithelial cells and immune cells. Mol Med Report. 2013 Dec;8(6):1635–42. DOI: 10.3892/mmr.2013.1726. PMID: 24126493.
14. McKim JM, Baas H, Rice GP, Willoughby JA, Weiner ML, Blakemore W. Effects of carrageenan on cell permeability, cytotoxicity, and cytokine gene expression in human intestinal and hepatic cell lines. Food Chem Toxicol. 2016 Oct;96:1–10. DOI: 10.1016/j.fct.2016.07.006. PMID: 27424122.
15. Weiner ML. Food additive carrageenan: Part II: A critical review of carrageenan in vivo safety studies. Crit Rev Toxicol. 2014 Mar;44(3):244–69. DOI: 10.3109/10408444.2013.861798. PMID: 24467586.
16. Liu F, Hou P, Zhang H, Tang Q, Xue C, Li RW. Food-grade carrageenans and their implications in health and disease. Comp Rev Food Sci Food Safety. 2021 Jul;20(4):3918–36. DOI: 10.1111/1541-4337.12790. PMID: 34146449.
17. 17. McKim, J. M., Willoughby, J. A., Blakemore, W. R., & Weiner, M. L. (2018). 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, 59(19), 3054–3073. https://doi.org/10.1080/10408398.2018.1481822