The food additive carrageenan (E 407), widely used in processed foods as an emulsifier and thickening agent and already found to cause chronic inflammatory bowel disease, ulcers, and increased blood sugar levels in animals, may pose risks to the gut health of humans as well, according to a study by the German Diabetes Center (DZD).
Researchers found that carrageenan consumption could increase intestinal permeability, potentially leading to inflammation and long-term health issues.
What Is Carrageenan?
Derived from red algae, carrageenan is a common ingredient in products like ice creams, sauces, and dairy substitutes.
Previous animal studies linked it to chronic inflammatory bowel disease, ulcers, and elevated blood sugar levels.
However, its effects on human health, particularly in relation to type 2 diabetes, remained unclear—until now.
Key Findings of the Study
In a clinical trial, 20 young, healthy men with a Body Mass Index (BMI) below 30 were given either carrageenan or a placebo as part of their normal diet.
The carrageenan dose was roughly two to three times the daily U.S. average. Over two weeks, researchers observed increased small intestine permeability in the carrageenan group, also known as “leaky gut”, likely due to inflammation.
“Our investigation suggests that carrageenan consumption can impair intestinal barrier function, similar to findings in animal studies,” said Prof. Robert Wagner, one of the lead researchers. “This could heighten the risk of inflammatory diseases over time.”
Impact of Carrageenan on Insulin Sensitivity
Although no significant overall changes in insulin sensitivity were detected, participants with higher body weight showed reduced insulin effectiveness, particularly in the liver.
These individuals also exhibited increased markers of inflammation in their blood and signs of hypothalamic inflammation, which affects sugar metabolism and appetite.
Call for Further Research
While the study participants were relatively healthy, the effects could be more pronounced in older or overweight individuals, noted Prof. Norbert Stefan. The researchers emphasized the need for further studies to better understand carrageenan’s health impacts.
“Given its widespread use, potential risks associated with carrageenan must be taken seriously,” concluded Prof. Wagner. “Understanding the effects of food additives is crucial for providing accurate health recommendations.”