A new study reveals that carrageenan, a widely used food thickener found in dairy and meat products, may increase intestinal permeability and affect insulin sensitivity in some individuals, raising concerns about its potential role in metabolic health.
Published in BMC Medicine | Estimated reading time: 4 minutes
Researchers at the University Hospital Tübingen conducted a randomized, double-blind trial investigating carrageenan (E407), an additive whose consumption has increased from 45mg to over 250mg daily since the 1970s. The study examined its effects on insulin sensitivity and gut health in 20 young, healthy men over two separate two-week periods.
The research team, led by Dr. Robert Wagner and Dr. Norbert Stefan from the German Center for Diabetes Research, found that while carrageenan didn’t significantly alter insulin sensitivity in all participants, it showed concerning effects in those with higher body mass indexes. Their findings suggest that body weight may influence an individual’s susceptibility to carrageenan’s metabolic effects.
The investigation revealed increased intestinal permeability following carrageenan consumption, suggesting possible inflammation of the gut barrier. For participants with higher body weight, researchers observed reduced insulin effectiveness, particularly in the liver, alongside elevated inflammatory markers in the blood and potential signs of hypothalamic inflammation – a brain region crucial for metabolism regulation.
“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,” explains Wagner. “This could have long-term health consequences and increase the risk of inflammatory diseases.”
The study utilized multiple sophisticated measurement techniques, including hyperinsulinemic-euglycemic clamps to assess insulin sensitivity and advanced brain imaging to detect inflammation. These methods allowed researchers to examine carrageenan’s effects throughout the body, from cellular responses to organ-level changes.
This research builds on previous animal studies showing carrageenan’s potential to induce glucose intolerance and exacerbate the effects of high-fat diets. The human trial’s findings suggest that while young, healthy individuals may tolerate carrageenan exposure, those with higher body weight might face increased metabolic risks from this common food additive.
Glossary
- Carrageenan (E407)
- A food additive derived from seaweed, commonly used as a thickener and stabilizer in dairy and meat products.
- Insulin Sensitivity
- The body’s ability to respond to insulin, with decreased sensitivity potentially leading to blood sugar regulation problems.
- Intestinal Permeability
- The gut’s ability to control what passes through its walls, with increased permeability potentially leading to inflammation.
Test Your Knowledge
How much has daily carrageenan consumption increased since the 1970s?
Daily consumption has increased from 45mg in the 1970s to over 250mg in recent years.
What was the duration of each treatment period in the study?
Each treatment period lasted two weeks, with a washout period between treatments.
What specific physiological changes were observed in participants with higher body weight?
They showed reduced insulin effectiveness in the liver, elevated inflammatory markers in the blood, and potential hypothalamic inflammation.
How might the study’s findings influence our understanding of food additive safety testing?
The results suggest that food additive safety may need to be evaluated differently for various population subgroups, as effects varied based on body weight despite all participants being non-obese.
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