Researchers have found that carrageenan(E 407), a common food additive used as an emulsifier and thickening agent, is linked to an increased risk of diabetes. A recent study revealed that it disrupts the intestinal barrier and impairs sugar metabolism.
Carrageenan belongs to the "Generally Recognized as Safe" (GRAS) food additive widely used in jellies, ice creams, puddings, nut milk, meat products, and yogurt. Earlier studies have shown carrageenan's links with chronic inflammatory bowel disease, ulcers, increased blood sugar levels, and insulin resistance in animals. In the latest study, researchers used clinical trials to investigate its effects on human health.
"Our investigation suggests that the consumption of carrageenan, similar to what has been observed in animal studies, can impair the barrier function of the intestine. This could have long-term health consequences and increase the risk of inflammatory diseases," explained Prof. Robert Wagner in a news release.
During the two-week trial, a group of 20 healthy participants were either given carrageenan in addition to their normal diet, roughly equivalent to two to three times the daily dose consumed in the USA, or a placebo. The researchers then measured health factors such as insulin sensitivity, brain inflammation, insulin resistance, intestinal permeability, and gut microbiome composition.
Although the researchers did not observe significant differences in overall insulin sensitivity between treatments, the effects of carrageenan varied based on body weight. In overweight individuals, it reduced insulin sensitivity and showed a tendency to increase brain inflammation. Carrageenan use was also associated with a more permeable gut lining. The researchers also found that it activated natural killer (NK) cells and triggered the release of inflammation-promoting cytokines.
"These findings suggest that carrageenan, a common food additive, may contribute to insulin resistance and subclinical inflammation in overweight individuals through pro-inflammatory mechanisms in the gut. Further investigation into the long-term health impacts of carrageenan and other food additives is warranted," the researchers concluded.
"Given the widespread use of carrageenan in foods, potential health risks should be taken seriously. It's important that we understand how food additives can affect our health in order to make informed recommendations to the public," cautioned Prof. Wagner.
