Carrageenan in Supplements: Facts vs. Fears

YAY for another fantastic Supplement Scoop topic thanks to a great question I received! I love nerding out about supplements, heh. 🤓

As health professionals, understanding the safety of any ingredient in supplements is crucial for guiding our clients effectively, including carrageenan. Given the concerns surrounding carrageenan due to misinterpretations about its potential impact on health, here is some context and clarity to help you make better informed choices about carrageenan in supplements.

SPOILER ALERT: This information may surprise you! 

Like always, any supplement links I share are clean links [aka affiliate-free] to ensure I continue to provide you with comprehensive, unbiased and agenda-free supplement information, as is in alignment with my integrity. 💜

Now let's dive in! 😀

Carageenan is a naturally occurring linear sulfated polysaccharide that is extracted from edible red seaweeds in the Rhodophyceae family. Carrageenan has been widely used in the processed food industry since the 1950’s for its gelling, thickening, and stabilizing properties, and has been mainly added to dairy and meat products due to the strong bond it forms with food proteins.

It’s not so simple as “carrageenan bad.” In fact, there are even some dietary carrageenan benefits (unless the carrageenan is poligeenan – more on that later)!

For context, I’ll start by summarizing this well-researched article by Dr. Axe, which provides a more balanced perspective on common carrageenan concerns. https://draxe.com/nutrition/what-is-carrageenan/

Here’s my summarized takeaways that Dr. Axe points out in his article I linked above:

Dr. Axe’s takeaways are:

As I mentioned earlier, there really are food-grade carrageenan benefits! That’s because natural carrageenan is a complex polysaccharide that is an indigestible fiber. Just like other indigestible fibers (inulin, as an example), carrageenan can cause gas and bloating in some individuals OR when eaten in high amounts. This is because, like other indigestible fibers, dietary carrageenan feeds the healthy microbiome in our intestines.

In other words, carrageenan is a prebiotic! 😀
(Did I just blow your mind? 🤯)  

However, just like anything and everything on the planet, some people can have a bad reaction to it. Therefore, the ingestion of food-grade carrageenan should be bioindividually assessed.  

For example, my body does not do well with most foods that contain inulin (like okra), but it does great with sea vegetables and carrageenan.  

As Dr. Axe points out, studies have shown that for *most* people, a diet that contains up to 5% carrageenan (which is a LOT), is not pro-inflammatory.  

But, as I said, how people react to anything is and always will be bioindividual. 

Poligeenan is a human-made, chemically degraded form of carrageenan produced through a chemical process involving:

These conditions fragment carrageenan’s natural molecular structure, reducing its molecular weight to 10,000–20,000 Daltons.  This results in the low viscosity, low molecular weight, sulfated polygalactan polymer known as poligeenan [aka polygeenan, poligeenane, hydrolyzed carrageenan, or degraded carrageenan].

Unlike carrageenan, poligeenan: 

In contrast, food-grade carrageenan retains its high molecular weight and helical integrity, ensuring it does not interact with tissue in the same inflammatory way as poligeenan due it being an indigestible fiber.

As noted in the abstract of THIS SCIENTIFIC REVIEW:
“Carrageenan (CGN) is a common food additive that has been widely used for decades as a gelling, thickening and stabilizing agent. Carrageenan has been proven safe for human consumption; however, there has been significant confusion in the literature between CGN and the products of intentional acid-hydrolysis of CGN, which are degraded CGN (d-CGN) and poligeenan (PGN). In part, this confusion was due to the nomenclature used in early studies on CGN, where poligeenan was referred to as “degraded carrageenan” (d-CGN) and “degraded carrageenan” was simply referred to as carrageenan. Although this nomenclature has been corrected, confusion still exists resulting in misinterpretation of data and the subsequent dissemination of incorrect information regarding the safe dietary use of CGN. The lack of understanding of the molecular weight distribution of CGN has further exacerbated the issue. The significant differences in chemistry, manufacture, and protein reactivity of CGN versus d-CGN and PGN are reviewed, in addition to the in vivo toxicological profiles of CGN, d-CGN, and PGN. As CGN cannot be hydrolyzed to PGN in vivo, concerns over the use of CGN as a food additive are unfounded, particularly since current studies support the lack of oncogenic and tumorigenic activity of CGN in humans.” 

In other words:
Due to the confusing way that carrageenan vs. degraded carrageenan vs. poligeenan was referred to for decades, some understandable misinterpretations of data occurred about natural, food-grade, and beneficial [to most] food-grade carrageenan, because it was mixed up with data from degraded carrageenan and poligeenan. 😬 

Poligeenan is a known inflammatory substance that researchers often use to test new anti-inflammatory drugs in the laboratory, and is not classified as a food additive.

Scientists worldwide have widely accepted that poligeenan can trigger cancer and other health issues.  

For example, poligeenan is listed as a Category 2B carcinogen by the International Agency for Research in Cancer [possible human carcinogen], which means the agency reviewed the evidence that poligeenan can cause cancer in animals and concluded that it could have the same effect in humans. Poligeenan is also included under Health and Safety Code section 25249.8 of the California Safe Drinking Water and Toxic Enforcement Act of 1986 (Prop 65).  

So, the good news is that understandable misinterpretation of data is why carrageenan got a bad rap. But, as you [hopefully] learned here today, that bad rap was completely unfounded and due to sloppy and confusing use of terminology in the past. Which means that unless your client is one of the few individuals who doesn't do well with sea vegetables, carrageenan in supplements is likely okay for them. YAY! 🥳

That concludes this Supplement Scoop!

I sincerely hope this information is helpful, colleague. 💜  

Until next time, remember that critical thinking + discernment is a SUPERPOWER. 🌟

Warm regards,
Kate 💜 

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

Weiner, M. L. (2014). Food additive carrageenan: Part II: A critical review of carrageenan in vivo safety studies. Critical Reviews in Toxicology, 44(3), 244–269. https://doi.org/10.3109/10408444.2013.861798  

National Center for Biotechnology Information. PubChem Compound Summary for Poligeenan. Accessed May 26, 2025. https://pubchem.ncbi.nlm.nih.gov/compound/Poligeenan  

Cohen, S. M., & Ito, N. (2002). A Critical Review of the Toxicological Effects of Carrageenan and Processed Eucheuma Seaweed on the Gastrointestinal Tract. Critical Reviews in Toxicology, 32(5), 413–444. https://doi.org/10.1080/20024091064282 

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The Supplement Scoop blog is written by Kate Mahoney, FNTP, FSS, a food-first dietary supplement expert, functional nutrition practitioner, and former international functional nutrition instructor with nearly 30 years of experience. Her mission is to empower everyone with the ability to identify the less than 15% of supplements worldwide that are worth using, with the hope that doing so will lead to improved supplement quality and effectiveness around the world. To that effort, in 2020, she founded the Supplement Academy to provide health professionals and consumers around the world with comprehensive and unbiased dietary supplement information and education.

In her free time, Kate is a Muppet whose inner spark is rejuvenated by nature, dancing to super loud music with friends, caring for her rescued feline furbabies with her beloved spouse, and enjoying delicious homecooked food with loved ones.