Should I worry about carrageenan in my food_blog title

This article explores the controversial food additive, carrageenan.  

Dueling researchers disagrees on the safety of this food additive.  

Read on to learn what some of the research has to say, where the governing bodies stand, and whether or not you should worry about carrageenan anyway!

Introduction to Carrageenan

First things first, let’s figure out how to pronounce it!  Let’s break it down: car·ra·gee·nan pronounced “kar-uh-gee-nuh n”.  If that still stumps you try listening here.

By Derek Keats from Johannesburg, South Africa [CC BY-SA 2.0 (],
via Wikimedia Commons

What the heck is it?

Carrageenan is a vegetarian food additive used to thicken and emulsify foods, similar to gelatin.  It comes from red seaweed, by heating and treating it with an alkaline solution.

Forms of Carrageenan

There are several forms, which differ in the way they are processed.  This results in two forms: one for food products and another not meant for consumption.


There are two food-grade forms of carrageenan (CGN):  refined and semi-refined.  

  1. Semi Refined:

In the semi-refined version, the seaweed is cleaned, heated and processed with an alkaline solution.  The end product includes carrageenan plus cellulose, a plant fiber. Due to less processing, the semi-refined version is faster and cheaper to produce.

  1. Refined:  
Refined carrageenan undergoes a second filtration and extraction, resulting in just carrageenan.   

Both forms are under the blanket term “carrageenan” in the United States.  The European Union (EU) differentiates them as E407- carrageenan (refined) and E407a- processed eucheuma seaweed (semi-refined).

Non-Food Grade

Degraded carrageenan (d-CGN) and/or poligeenan (PGN) are forms of carrageenan not meant for human consumption.   This form is processed differently than the food-grade version, resulting in different properties and uses (1).   

For the purposes of this article, we will talk about food-grade carrageenan and refer to it as carrageenan or CGN.

Foods that Have Carrageenan

Seemingly innocent, carrageenan can be found in many common foods and packaged foods.  Below are some examples:

Dairy Products:

  • Cheese
  • Ice cream
  • Yogurt
  • Chocolate milk
  • Cottage cheese
  • Coffee creamer
  • Cream
  • Half and half

Non-dairy sources:

  • Milk alternatives (almond, soy, coconut, etc.)
  • Vegetarian meat alternatives
  • Vegan cheeses
  • Meal replacement drinks, like Ensure
  • Deli meats
  • Processed meats
  • Infant formula


  • Sauces
  • Salad dressings
  • Syrup

Pull out your favorite dairy products, non-dairy alternative, or packaged food and read the label to see if it contains carrageenan.

What’s The Carrageenan Controversy All About?

Conflicting research exists about health and safety concerns over dietary consumption of CGN.  

Study design, methods, and types of CGN solutions impacts the results, leading to controversy and confusion.  Below highlights a few of these controversies.

Heavy Metals and Carrageenan

A 2010 study found CGNs have strong metal-binding properties in aqueous solution.  The study suggests promise with CGN in medicine to bind and remove metals from the body (2).  

With that said, what about heavy metals from the environment binding to seaweed used for carrageenan?  Seaweeds harvested for consumption may contain heavy metals. Metal concentrations may be highly variable depending on the region of where the seaweed is grown and environmental factors. Regulations on allowable limits vary depending on the country, if any exist at all (3).

Seaweed used for CGN production tested by the FDA in 2014 for lead, arsenic, and cadmium found low levels of these metals below established thresholds.  However, adverse health effects, such as developmental delays in children have been linked to heavy metal exposure (4).  Additionally prenatal exposure to heavy metals may result in adverse birth outcomes (5).

It is unclear if the FDA performs routine testing of heavy metals in carrageenan because it is considered a food additive and not a food.  More information on metals testing by the FDA can be found here.  

TAKEAWAY:  Those with compromised immune function/chronic health conditions, pregnant women, children, and the elderly may want to avoid additional unnecessary exposure of heavy metals through food, such as carrageenan.

Gut and Colon Health Influence

Studies suggest a link between CNG and gut health.

The compounds in red seaweed act as dietary fiber (6).  The fiber may act as a prebiotic, which can influence gut health.  Research in animals suggest the fibers in the seaweed may induce anti-inflammatory and beneficial changes in gut bacteria (6, 7).  

Opposing research points to the pro-inflammatory effects of CGN consumption in animal models (8).  Evidence shows the link between PGN/degraded carrageenan to intestinal lesions and colonic tumors. The study suggests dietary CGN can change to the pro-inflammatory form through digestion.  It also suggests contamination of dietary CGN with small amounts of degraded carrageenan, resulting in negative health consequences (8).  

The research further suggests an individual’s unique intestinal bacteria makeup may determine how CGN acts in the body (8).  What this means is that it is impossible to determine how an individual will respond to CGN consumption.

There is no set dose for CGN consumption in the United States.  However, a 2014 study found that “CGN at doses up to 5% in the diet does not induce any toxicological effects other than soft stools or diarrhea, which are a common effect for non-digestible high molecular weight compounds” (9).   

TAKEAWAY:  Research has shown both pro- and anti-inflammatory gastrointestinal effects in animal models with no clear conclusion.  Those with gastrointestinal disorders and symptoms may want to avoid CGN or remove it from their diets to see if they notice a difference.

Insulin Response Influence

Studies suggest a link between CGN and blood glucose levels.

The influence of prebiotics in CGN may improve gut bacteria.  As gut bacteria improve, this may result in improving blood glucose levels by regulating insulin response (7).

Opposing research found increased fasting blood glucose levels in mice when exposed to CGN in drinking water in as little as 6 days (10).  Additionally mice exposed to CGN and fed a high fat diet showed increased levels of non-HDL cholesterol, total cholesterol, and accelerated high blood glucose.  CGN-induced inflammation in combination with a high fat diet may increase blood sugar levels and lead to insulin resistance (10).


TAKEAWAY:  Inflammation may play a role in how CGN affects blood glucose levels and may vary by individual.

What do Governing Bodies say about Carrageenan?

The FDA’s Stance

Carrageenan, while approved by the Food and Drug Administration (FDA), has no set limits (listed as “in the amount necessary” for use) in the United States.

The FDA takes the stance of approval of an additive when there is “reasonable certainty of no harm.”  However the FDA also states:

“Because of inherent limitations of science, FDA can never be absolutely certain of the absence of any risk from the use of any substance. Therefore, FDA must determine – based on the best science available – if there is a reasonable certainty of no harm to consumers when an additive is used as proposed.”  

Interestingly, controversy sparked in 2018, as the FDA rejected a 2016 decision by the USDA’s National Organic Standards Board to remove carrageenan from a list of approved organic substances.   

The European Union’s Stance

The European Food Safety Authority has set a temporary limit of 75 mg/kg of body weight per day for CGN consumption, set in 2018 due to lack of certainty in the data. They plan to reevaluate this every 5 years.

Unlike the US, the EU does not allow carrageenan as an ingredient in infant formula.  The decision cited lack of data on how CGN affects intestinal absorption in infants.

So, Should I Worry About Carrageenan?

There is not a conclusion about carrageenan that researchers agree on at this time.  A recent 2018 review detailing gaps and disagreements in the current data elicited comments, further fueling this debate (11,12).  

Given the possibility of an inflammatory effect on gut barrier function, the potential risk of heavy metal exposure, and potential influence on blood sugar regulation, a cautionary approach may be best.  Additionally, coupled with the lack of information on acceptable daily intakes in the US, certain populations may want to avoid it.

These may include:

  • Infants
  • Children
  • Pregnant and lactating women
  • The elderly
  • Those suffering from bowel disorders
  • Those with chronic health conditions

As a mom of young children, I take a cautious approach.  Little bodies take on more of a toxic load. I stick to buying mainly unpackaged, whole foods.  When I do buy packaged foods, I look for the least ingredients as possible and skip those that include carrageenan.   After all ice cream should just be ice cream!

If you decide to avoid carrageenan in your diet, refer to this buying guide by the Cornucopia Institute to help you navigate products without carrageenan.  Check product labels for this ingredient so you can be an informed consumer.

Want more gut healing support? Check out my online course: Heal Your Gut in 30 Days!

Guest Contributor Courtnay Mecca, MS, CNS Candidate