Concerned About Carrageenan

After doing some quick google searches on carrageenan I’m not sure it’s something I’d like to add into my daily diet. Even undegraded carrageenan seems to be somewhat controversial. Was curious on what other people were thinking about this new additive? Should I be concerned? Also I feel that adding this is contradictive to the spirit of soylent. I thought it was more focused on health than taste. Could there be a better alternative?

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Suggest one?

From Food Science Matters, “An overwhelming body of evidence supports the conclusion that carrageenan is safe and suitable for use in food. Regulatory authorities in every region of the world including the United States, Europe, China, Japan and Brazil have found carrageenan safe for use in food.”

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Actually it has been focused on nutrition not health.

Google searches for things like ingredients in Soylent should never be quick. Quick searches will only get you the sensationalized click bait.


And not to be racist (followed by something racist) I don’t think a country like Japan, with a culture around purity and an average lifespan that makes immortal gods look frail, is going to incorporate any dangerous additives to their national diet. Actually, I read a book about Japan recently and they made a point about how rough the Ministry of Health and Welfare is (Japanese FDA) to get to approve anything, as opposed to only needing a few good trials with many discrepancies in the U.S.

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I am cancelling my subscription until carrageenan is removed in a future version. I have had problems with “food grade carrageenan” in the past, when I was trying to eliminate dairy and get calcium from fortified vegetable “milk” of various sources and brands; I was having terrible intestinal pain. I do not trust carrageenan, regardless of quality. It is too controversial and the risks are not worth it to me.

“Carrageenan has been the subject of significant investigation for several decades, and the complexity pertaining to it may have impeded our ability to form a clear impression about its harmful effects. In rodent models, there is clear evidence that degraded carrageenan can induce ulcerations and neoplasms. Also, there is clear evidence that food-grade carrageenan can be broken down to degraded carrageenan by acid hydrolysis and by bacteria, and degraded carrageenan is likely to contaminate foodgrade carrageenan.

(I am unable to copy/paste from this paper, please read pages 219 and 220. Screenshot below.)

(EDIT: Oh my god, I love Google Docs… OCR text pasted here:)

Degraded and undegraded carrageeman exposures

Regulatory issues pertaining to the incorporation of carrageenan in foods have largely been confined to considerations related to degraded carrageenan. This appears to be due to the many studies that have been conducted in animals that clearly demonstrated the toxic effects of exposure to lower molecular weight carrageenan. By lower molecular weight, investigators have generally considered carrageenan of under 30000-40000 molecular weight, although others consider low molecular weight carrageenan to have molecular weight less than 100 000 (Marrs, 1998).

The available evidence suggests that ingestion of food-grade carrageenan invariably is associated with exposure to low molecular weight forms. The reasons for this include:

1 food products that contain food-grade carrageenan contain degraded carrageenan (Ekstrom, 1985; Ekstrom et al, 1983; Marrs, 1998)

2 acid digestion such as occurs in the stomach is sufficient to break down higher MW forms of carrageenan to lower MW (Ekstrom, 1985; Ekstrom et al, 1983; Yu et al, 2002)

3 bacterial action is able to break down carrageenan (Sarwar et al, 1987; Weigl and Yaphe, 1986)

4 heat exposure, such as can occur with consumpt on of warmed beverages or preparation of food products, leads to degradation of carrageenan (Marrs, 1998).

These four processes lead to the availability of low molecular weight carrageenan from the higher molecular weight forms.

Gastrointestinal metabolism of carrageenan to form smaller molecular weight components has been observed by several investigators, who reported that carrageenan of high molecular weight changed during intestinal passage, compatible with a process of hydrolysis yielding lower molecular weight components (Ekstrom, 1985; Ekstrom et al, 1983; Engster and Abraham, 1976; Pittman et al, 1976; Taché et al, 2000).

In the lab, food grade carrageenan is safe; I do not argue that. I doubt ingested carrageenan of any quality is safe due to processes of digestion.


To be fair, as an equal opportunity skeptic, the Food Science Matters site is the product of a publicly traded chemical manufacturer. Though I am not convinced carrageenan is either safe or unsafe, I have a hard time taking facts from a source that has incentive to be biased.

I’ve seen the research posted by @horsfield (which concludes it is safe) as well as the letter posted by @drparent (which argues it is unsafe). When I start seeing everyone hanging their hat on the same piece of research it sets off some alarm bells. Still, given the controversy, it’s a bit concerning they added this ingredient to Soylent 1.5.

I don’t have access to either of the full text reports from @horsfield. Has anyone read them in full or know of other research on the topic?


I love the texture of carrageenan. I’m gonna eat it up.

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I have found plenty of support for the safety of undegraded carrageenan on cells and the toxicity of degraded carrageenan on cells. Here is one example:

The authors declare that they have no competing interests.
Full Text, "Cytotoxicity effect of degraded and undegraded kappa and iota carrageenan in human intestine and liver cell lines":


I have found some support for the toxicity of both degraded and undegraded carrageenan in animals via digestion:

I reviewed from established sources mechanisms for production of degraded carrageenan from undegraded or native carrageenan and data with regard to carrageenan intake. Review of these data demonstrated that exposure to undegraded as well as to degraded carrageenan was associated with the occurrence of intestinal ulcerations and neoplasms. This association may be attributed to contamination of undegraded carrageenan by components of low molecular weight, spontaneous metabolism of undegraded carrageenan by acid hydrolysis under conditions of normal digestion, or the interactions with intestinal bacteria.
No mention of interest.

Full text available here:


@ranger94 : Here is the Full Text of one paper posted by @horsfield , which is the support for the safety of undegraded carrageenan in animals via digestion:

Declared interest:

The current review was prepared for FMC Corporation under a cost reimbursable contract. FMC Corporation is a manufacturer of CGN and products containing CGN.
"Food additive carrageenan: Part II: A critical review of carrageenan in vivo safety studies." :

May I ask @drparent if your problems with even food grade carrageenan are similar to what I wrote about in this thread (To compare possible 1.5 issues with others)? You mention intestinal pain, but did the issues go further than that? I’m trying to pinpoint an apparent issue my body is having with 1.5 and I think I’m closing in on carrageenan as being a culprit. More testimony to compare would help as it seems such reactions to carrageenan isn’t very common.

The more I read on the subject the more cautious I am of the ingredient. If I do pinpoint my issues with carrageenan I may also have to consider suspending my soylent subscription as I do not want to live with these issues.

Please and thank you @drparent for a possible response. Please and thank you if you don’t give one either. Just thank you for the time.

When I was having trouble with carrageenan, it was not a part of my diet at every meal, only in the nondairy milks I was drinking for adequate calcium (soy, almond, and especially coconut). I didn’t notice much of a difference with gas then, but I wasn’t on a consistent diet day to day, either, so some days gas was worse and some days better, and it was caused by a variety of foods (legumes were the biggest culprits). When I focused on finding out what was causing the intestinal issues, I read about the possibility of carrageenan being the cause, found a nondairy milk without carrageenan, and voila, no more pain. (I did try eliminating other stuff first, like nuts and legumes and wheat, but that had no effect. Reintroducing those items after eliminating carrageenan did not cause pain.) I imagine that if I was consuming carrageenan at every meal, it would have progressed to diarrhea, but I cannot say for sure.

Recently, however, I tried an experiment: I bought a soymilk with carrageenan and drank one serving per day for three days. I had pain starting 4 hours after the first serving and lasting for 4 days for most of the day, along with excessive gas on and off. The rest of my diet was the 1.4 I have stockpiled, tea, Chipotle (brown rice, black beans, tofu, gucamole, pico de gallo, and lettuce), and I had a few pints of beer on day 2 (my normal diet for the last few months). Gas was worse after beer, as usual. I threw out the remainder of the soy milk. I have not had pain or excessive gas since (just the increase I’m used to after a couple pints). I am convinced I am sensitive to carrageenan, but in the interest of science I am willing to try a different nondairy milk upon request. I still have a one month supply of 1.4 and am trying to stretch it.

@SkullAndCostBones : if you are so inclined, try eliminating carrageenan and reintroducing it. Ideally, if you have any 1.4 or can get some, try consuming that with and without another source of carrageenan. I’m willing to trade you 4 packets of my 1.4 for 4 of your 1.5 if you’d like, but only if you are willing to do the experiment with me. I’d go 100% 1.5 and see what happens, you’d go 100% 1.4 until you feel better, then introduce an outside source of carrageenan (hopefully you can get there in 4 days, I don’t really want to let go of more of my supply than that :confused: ).

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I love the idea of the experiment but I will have to politely decline it. Aside from the “internet stranger danger” thing and the like I’d hate to widdle down your 1.4. I have a single bag left that I was saving for a special occasion in case 1.5 was awful. 1.5 tastes fine but, well, I’ve already went over the issues.

Thank you very much for the proposition as well as giving me further details! Very informative and I think will prove most helpful. I will look into a way to adjust onto a daily carrageenan, non-soylent diet as a test. Though I haven’t had traditional food in some time so such an task could take several weeks to get adequate results.

This proposed carrageenan sensitivity appears to only be affecting a minority of soylent users on this board. I feel if carrageenan is indeed the horrid culprit that our numbers could be too insignificant to encourage a change in recipe. I wonder what all is factored into ingredient changes as far as customer feedback goes?

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Historically, a small but vocal minority have had allergy / intolerance issues with a variety of ingredients. Most who are vocally opposed are just chemophobes, but there have been reports of real digestive tract issues as well. I think that the chemophobes undermine legitimate concerns, and unfortunately it’s very difficult to verify claims of actual intolerance; digestion is complicated. (Strictly scientifically, I know that I can’t say for sure that carrageenan is the real cause of my issues, just that its strongly correlated so far.) RL has mostly made adjustments only to meet its original stated goals (nutritional balance, all vegan ingredients, neutral taste and texture). I’m not sure how much comes from customer feedback and how much comes from just Rob and others at RL playing with ingredients over time. I do know that the addition and subsequent removal of the enzyme blend (1.2 & 1.3, I think) was influenced by customer feedback.


Soylent 2.0 does not contain carrageenan! Hooray! My preorder has been placed :wink:

Looking forward to the new version, thank you (whether anyone who matters heard me or not).

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