You may have heard that carrageenan as a food additive isn’t safe.
And then you look at the ingredient list of some skin care products, and there it is.
So now you’re wondering: Is this an ingredient I should avoid? Or have the rumors concerning its safety risks been exaggerated?
Let's start with the basics.
What is Carrageenan?
We typically find carrageenan in foods like yogurt, salad dressing, pudding, ice cream, chocolate milk, infant formula, sauces, and other food items that are smooth and consistent.
Carrageenan is extracted from red seaweed (Chondrus crispus), which is commonly called Irish moss. The ingredient isn’t exactly Irish moss, though. Rather, it’s an extract from the plant, an isolated polysaccharide that’s used as a thickener and emulsifier in foods. Add carrageenan to something and you improve the texture and help the ingredients mix together more smoothly.
“Spoon-hugging” texture? Carrageenan helps with that. It also helps keep oil and water-soluble ingredients from separating, keeping the overall product more stable. This is why it’s often used in salad dressings and sandwich spreads that include both oil and water-soluble ingredients.
It’s no wonder, then, that the ingredient would also be used in skin care products to give them a smooth, creamy texture.
Carrageenan is also a water-binding agent, which means it helps hold water onto the skin and hair, increasing hydration. You’re likely to find it in products like moisturizers, shampoos, conditioners, and toothpastes.
How is Carrageenan Processed?
Carrageenan may be processed in one of two ways:
Refined: The raw materials are cooked in an alkaline solution. The solid parts are then filtered out. The remaining solution contains the carrageenan, which is then concentrated, removed from the solution, and dried.
Semi-refined: The raw materials are cooked in an alkaline solution that contains potassium hydroxide. This prevents the carrageenan from dissolving in the solution, so that when the algae are removed, what is left is carrageenan and cellulose, which is ground into a powder.
Is Carrageenan Safe?
The concerns about carrageenan involve mostly “degraded” carrageenan, which is not used in food or cosmetics. Degraded carrageenan is made in a lab by taking food-grade carrageenan and hydrolyzing it—breaking the bonds and making the molecules smaller.
Degraded carrageenan was created in the 1960s. At that time, doctors often recommended carrageenan for to treat peptic ulcers. But the concentration you needed in order for it to be effective was thick and unpleasant to consume, so researchers degraded it to make it easier to take.
They soon found that this wasn’t a good solution, and that degraded carrageenan was harmful. It’s thus no longer used to treat peptic ulcers.
The concern about carrageenan came up again in the early 2000s in relation to research by Joanne K. Tobacman, M.D. She published a study review in 2001 that showed a connection between exposure to degraded carrageenan and stomach ulcers and tumors in mice. Degraded carrageenan was also related to inflammation and other problems in colon cells.
Tobacman also expressed concern about food-grade carrageenan, noting that some of her research found it was also associated with intestinal ulcers. She gave the following reasons for this finding:
- The food-grade carrageenan could be contaminated with degraded carrageenan.
- Digestive processes and intestinal bacteria could interact with it in such a way as to result in degradation and subsequent intestinal inflammation. We have no evidence that this happens in living organisms, however. Tobacman draws these conclusions from laboratory studies that simulate gastric acid effects on carrageenan.
The animal studies referenced by Tobacman also involved levels of carrageenan that made up between 2.5 and 15 percent of the rats’ total diet, whereas the carrageenan in human diets make up a much smaller fraction.
In 2008, Tobacman filed a petition with the FDA urging them to reconsider the safety of the ingredient. The FDA disagreed with her findings, and maintains that carrageenan is safe. Some scientists have also argued that animals have very different intestinal symptoms than humans, and that we can’t draw conclusions without human studies—particularly when degraded and food-grade carrageenan are so different.
What About Carrageenan in Skin Care?
Though the above results are concerning, they are:
- Shown only in animal studies (not human).
- Come from one main researcher.
We also have to remember that these are just a few concerning animal studies stacked up against countless other studies showing carrageenan to be safe. Authorities in the U.S., Europe, China, Japan, Brazil, and more find the ingredient safe for use in food.
Customers with gastrointestinal sensitivities may choose to avoid carrageenan in their diets. But do we need to be concerned about this ingredient in skin care products?
Remember that cosmetic companies are allowed to use only food-grade carrageenan in their products—degraded carrageenan isn't allowed.
Further, carrageenan is too large a molecule to be absorbed through the skin, so you don’t have to worry about it getting into your bloodstream and affecting your gut.
Meanwhile, carrageenan may actually prove beneficial to skin in several ways. In addition to its hydrating properties, it’s also been found in some studies to block the growth of viruses like human papillomavirus, making it potentially even more protective in sexual lubricants (in which it’s already included).
The Environmental Working Group gives the ingredient a safe, low-hazard rating of “1” on its Skin Deep Database, and the European Cosmetics Directive permits it for use in cosmetics. And in 2014, The Joint Expert Committee on Food Additives (JECFA)—which advises the World Health Organization (WHO)—after completing an in-depth review of the science related to the safety of carrageenan, found it safe for use in food, including infant formula.
If it’s considered safe even for infants to consume, we don’t think you have to worry about it in skin care products.
What do you think of carrageenan? Were you worried about it in skin care products?