• Carrageenan (E407), a thickener in soy milk, milkshakes, and ice cream may reduce insulin sensitivity and disrupt blood sugar control.
  • It can increase gut permeability, potentially leading to inflammation and higher risks of heart disease and type 2 diabetes.
  • Researchers suggest the impact could be stronger in older or overweight individuals, warranting caution and further studies.

Carrageenan or E407 – a widely used food additive commonly found in soy milk, milkshakes, and ice cream may increase the risk of type 2 diabetes, according to a new study.

Carrageenan is used in the food industry as a thickening and emulsifying agent because of its gel-like consistency.

However, concerns are growing about its impact on health, particularly its effects on gut health and blood sugar regulation.

Researchers from Heinrich Heine University Düsseldorf in Germany explored whether carrageenan could influence the risk of developing type 2 diabetes.

The study involved 40 healthy men aged 27 to 31.

Participants were divided into two groups: one received 250mg of carrageenan daily for two weeks alongside their regular diet, while the other received a placebo.

At the end of the trial, researchers conducted MRI scans of the participants’ brains and guts to assess inflammation and measured their insulin sensitivity, a key marker of diabetes risk.

Insulin is the hormone responsible for stabilising blood sugar levels and allowing cells to absorb energy from food. In type 2 diabetes, the body becomes resistant to insulin, leading to unstable blood sugar levels.

The study revealed several concerning outcomes for those consuming carrageenan, particularly in participants with higher body weight:

  • Those in the carrageenan group showed a slight reduction in insulin sensitivity, particularly in the liver, compared to the placebo group.
  • MRI scans identified inflammation in the hypothalamus, the part of the brain that regulates sugar metabolism and appetite.
  • Participants consuming carrageenan experienced increased permeability of the small intestine, allowing harmful bacteria to pass into the gut – often referred to as a “leaky gut” and linked to conditions such as heart disease and type 2 diabetes.

Professor Robert Wagner, a co-author of the study, explained: “Our investigation suggests that the consumption of carrageenan can impair the barrier function of the intestine, similar to what has been observed in animal studies. This could have long-term health consequences and increase the risk of inflammatory diseases.”

While the changes observed in insulin sensitivity were modest, Professor Norbert Stefan noted that the participants were likely “too healthy” to exhibit significant metabolic effects.

He added that the impact could be much stronger in older or overweight individuals, highlighting the need for further research.

Carrageenan is not the only ingredient under scrutiny.

Previous studies have raised concerns about emulsifiers in ultra-processed foods. These chemicals can disrupt the gut’s natural balance by creating gaps in the protective gut lining, increasing the risk of bacterial infections.

This study adds to the growing evidence that ultra-processed foods and their additives may pose risks to metabolic and gut health.

Reducing your exposure to E407

  • Look for “E407” or “carrageenan” in ingredient lists.
  • Focus on minimally processed foods like fresh vegetables, fruits, lean proteins, and whole grains.
  • Consider making your own plant-based milk or ice cream at home to control ingredients.

For more tips and updates, explore our Healthy Eating Section.

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