A new study suggests potential health risks associated with carrageenan (derived from red seaweed), a common food additive used as a thickener and found in everything from ice cream to plant-based milk.

Researchers found that overweight people who ate foods with the additive became more insulin resistant and had more inflammation.

“In overweight participants, carrageenan exposure resulted in lower whole body and hepatic insulin sensitivity,” the study authors wrote, highlighting the need for further investigation into food additives that consumers might consider harmless.

Carrageenan Linked to Reduced Insulin Sensitivity, Inflammation

The research, published in BMC Medicine on Nov. 26, was a randomized, double-blind, placebo-controlled trial involving 20 young, healthy male participants who received either 250 milligrams of carrageenan or a placebo twice daily over two weeks.

Key outcomes of the study included the measurement of insulin sensitivity through various tests, including the oral glucose tolerance test. Although no significant differences in overall insulin sensitivity were observed among all participants, interactions between participants’ body mass index and their exposure to carrageenan or the placebo were notable.

In overweight people, carrageenan led to lower insulin sensitivity, increased brain inflammation, and higher levels of inflammatory markers (C-reactive protein and interleukin-6).

Carrageenan was linked to increased intestinal permeability, suggesting that the participants’ digestive systems might allow substances to enter the bloodstream more easily. The study also showed immune cell activation and increased pro-inflammatory proteins released from white blood cells after carrageenan exposure. This supports the theory that the additive may influence insulin sensitivity by fostering inflammation.

While existing research demonstrates carrageenan’s correlation with heightened metabolic risks, inflammation, and gut disruption, the precise molecular mechanisms driving these adverse effects remain unclear.

While previous animal studies had suggested that carrageenan could induce glucose intolerance and worsen the adverse effects of high-fat diets, the new study represents one of the first clinical investigations into the additive’s effects on human glycemic response.

The researchers called for further research into the long-term health effects of carrageenan and similar food additives, particularly in populations at higher risk for developing Type 2 diabetes.

Cutting Out Carrageenan

Carrageenan is fairly common in highly processed foods, dairy products such as chocolate milk and ice cream, and plant milks, Stephanie Schiff, a registered dietitian and certified diabetes care and education specialist at Huntingdon Hospital, a part of Northwell Health in New York, told The Epoch Times.

The additive can be easily avoided if you’re eating a diet based on whole foods that are as close to their natural state as possible, she noted.

“If a food is made in a factory and has ingredients that are not familiar or are difficult to pronounce, it is likely highly processed and may contain carrageenan,” Schiff said. “If you’re eating a packaged good that is creamy or thick, check the label; it may contain carrageenan.”

Although carrageenan is approved by the Food and Drug Administration, Schiff noted that it has no nutritional value.

Schiff also recommended a whole-food, plant-focused diet to circumvent carrageenan and other unhealthy additives. Alternatives such as gellan, locust bean, guar, and xanthan gums can be used in place of carrageenan without the associated health risks. However, she cautioned that buying organic does not guarantee that a product is free from carrageenan.

The amount of carrageenan in a typical Western diet can range from 250 milligrams to 2 to 4 grams per person per day. Carrageenan is the fourth-most commonly consumed food additive in pediatric patients with Crohn’s disease, according to research.

The U.S. Department of Agriculture (USDA) currently allows carrageenan in organic food, despite opposition from the National Organic Standards Board (NOSB), a federal advisory board that makes recommendations on organic food and products.

Carrageenan Isn’t the Only Additive of Concern

According to Schiff, people should be aware of other additives commonly found in processed foods, including:

• Sodium Nitrite: Found in processed meats, nitrites have been linked to a higher risk of several types of cancer when heated.
• High-Fructose Corn Syrup: This sweetener is associated with weight gain, diabetes, and inflammation.
• Trans Fats: Present in hydrogenated and partially hydrogenated oils, these fats can increase the risk of heart disease, stroke, and diabetes.
• Monosodium Glutamate (MSG): MSG can cause sweating, flushing, numbness, palpitations, and tingling in sensitive individuals.