August 7, 2008

You Ask, I Answer: Carrageenan

Here is another food label question for you.

The soy milk I drink (Silk unsweetened) has carrageenan listed as an ingredient. What is that?

Someone I work with told me it causes cancer.

-- Miriam Scorfi

Chicago, IL

Carrageenan is an extract from a red seaweed species native to the coast of Ireland.

It does not add to -- or detract from -- the nutrient content of a given food, but is primarily used to thicken and emulsify.

In your soy milk's case, carrageenan is used to give it a creamy mouthfeel (this is why an iced latté made with Silk unsweetened soymilk has a much creamier texture than one with non-fat cow's milk).

Mind you, it is not simply vegan alternatives to milk that contain this extract.

It is found in condensed milk as well as in some ice creams, yogurts, baked goods, and toothpastes.

Let's now talk about your coworker's alarming cancer claim.

He or she must be referring to a literature review of 45 studies penned by Dr. Joanne Tobacman (assistant professor of clinical internal medicine at the University of Iowa at the time) that was published in the October 2001 issue of the Environmental Health Perspectives journal.

Dr. Tobacman concluded that carrageenan was not entirely safe and could cause gastrointestinal disorders (as well as increase risk for stomach cancers), since applied heat during preparation -- as well stomach acid during digestion -- can degrade it into a substance known as poligeenan.

However, two years later, the Joint FAO/WHO Expert Committee on Food Additives concluded that carrageenan was safe for consumption.

Mind you, JECFA originally came to that conclusion in 1998, but reopened the case after reading Dr. Tobacman's paper.

One sticking point was that when the dosage of carrageenan fed to rats in the literature Dr. Tobacman reviewed was converted to an equivalent measurement for humans, it was an outrageously high figure that would be impossible to consume on a daily basis.

The report downright concludes that "in long-term bioassays, carrageenan has not been found to be carcinogenic, and there is no credible evidence supporting a carcinogenic effect or tumor-promoting effect on the colon in rodents."

Some scientists have also theorized that the intestinal bacteria of rats (different from that of humans) may have been a significant factor in the degradation of carrageenan witnessed in the literature reviewed by Dr. Tobacman.

By the way, JECFA is made up of toxicologists and other scientists from 10 different countries (including Norway, Japan, Australia, and the United States.)

When carrageenan is used in its unadulterated form, it is perfectly safe. Therefore, I don't perceive a glass of Silk soymilk -- or a splash of it in your cereal -- to be a health hazard. There are far more important things to worry about.

I suggest your co-worker look up the word "hyperbole" in the dictionary.


HangryPants said...

Thanks for the great info, I was just wondering about this myself.


Norma said...

Good info. Thanks.