Some substances don’t mix naturally, like oil and water. But many recipes require these incompatible ingredients to be presented together. That’s where emulsifiers come in. These substances allow foods like salad dressings, baked goods, and ice cream to come to life — and they can harm your health.
This is the main takeaway from several recent studies. Data suggests that emulsifiers may impact your gut microbiome and even impact your brain.
However, emulsifiers are found in a wide range of processed foods, such as salad dressings, baked goods and flavored drinks, making them difficult to avoid. Here’s what the data shows on emulsifiers and how concerned you should be about them.
What are emulsifiers?
Emulsifiers are food additive molecules that prevent the separation of liquids that do not usually mix. These ingredients help “give foods the texture and consistency consumers expect,” according to the Food and Drug Administration (FDA).
There are many emulsifiers in the food chain, but some of the most common options include guar gum, lecithin, and carrageenan. Emulsifiers carry the FDA GRAS (or “generally recognized as safe”) designation, which means that qualified experts have deemed them safe when used as intended.
What does the data show?
In recent years, research has suggested that emulsifiers are bad for the gut and even the brain.
A recent study, published in the journal Nature Communications Biology in June 2024 analyzed the impact of several emulsifiers on mice and found that the additives were linked to body inflammation, as well as higher blood sugar levels and insulin resistance, which can lead to diabetes. Synthetic emulsifiers appear to cause more harm than natural emulsifiers, according to the results.
Another study, this one published in the journal BMC Microbiomeanalyzed the impact of several emulsifiers on intestinal cells. The researchers concluded that “many, but not all, commonly used emulsifiers may directly alter the gut microbiota in ways that may promote intestinal inflammation.” This particular study found that the emulsifiers polysorbate 80 and carboxymethylcellulose were linked to the greatest disruption of the gut microbiome, as well as inflammation.
But the impact of emulsifiers can go beyond the gut. A study published in the journal Brain, behavior and immunity analyzed the impact of polysorbate 80 emulsifier on mice and determined that the ingredient disrupted the blood-brain barrier. The researchers concluded that the study found “strong evidence” that a diet-induced imbalance in the gut microbiome “may be a risk factor for age-related cognitive decline.”
Benoit Chassaing, PhD, researcher in emulsifiers and head of microbiome/host interactions at the Institut Pasteur
By disrupting the delicate balance of gut bacteria, these compounds can trigger a chain reaction of health problems that extend far beyond the gut.
— Benoit Chassaing, PhD, emulsifier researcher and head of microbiome/host interactions at the Institut Pasteur
Why might emulsifiers interfere with your gut and brain?
Research into this is ongoing, but there are some things to consider. “Evidence indicates that certain emulsifiers directly affect microbial communities in the gut,” explains Benoit Chassaing, PhD, emulsifier researcher and head of microbiome/host interactions at the Pasteur Institute. “These compounds can selectively disrupt the balance of microbes, killing beneficial bacteria while creating an environment in which harmful bacteria, particularly those with pro-inflammatory tendencies, can thrive.”
Basically, emulsifiers can encourage bad bacteria or inflammatory bacteria to grow while interfering with the good bacteria in your gut, says Molly Rapozo, RDN, senior nutrition and health educator at the Pacific Neuroscience Institute at Providence Saint John’s Health Center in Santa Monica, California. This could have “broader health implications,” says Chassaing, which could include changes to your metabolism and immune system.
“Some emulsifiers also disrupt the protective barrier of the intestine,” explains Rapozo. The impact of this isn’t entirely clear, but it could potentially have a negative influence on your overall health, including your brain, she says.
Still, it is difficult at this point to say that emulsifiers alone will cause the development of dementia or Alzheimer’s disease. “The exact cause of Alzheimer’s disease is not completely understood,” says Verna Porter, MD, neurologist and director of the department of dementia, Alzheimer’s disease and neurocognitive disorders at the Pacific Neuroscience Institute at Providence Saint John’s Health Center in Santa Monica, California.
The biggest concern right now is that emulsifiers and other additives can lead to chronic inflammation of the gut, says Chassaing. “This inflammation is not limited to the gut: it can act as a catalyst for a variety of chronic diseases, including inflammatory bowel disease (IBD), metabolic syndrome, and even conditions like diabetes and cardiovascular disease.” , he said. “Essentially, by disrupting the delicate balance of gut bacteria, these compounds can trigger a chain reaction of health problems that extend far beyond the gut. »
How to take care of your gut microbiome
Experts emphasize the importance of supporting your gut microbiome. “One of the most effective measures is to reduce or eliminate the consumption of ultra-processed foods, which often contain emulsifiers and other potentially harmful additives,” says Chassaing.
Ultra-processed foods are significantly altered from their natural state. They usually contain sugar, oil, salt or other substances, as well as artificial colors and flavors, preservatives and other ingredients, which are added to preserve their texture and longevity.
“Focus instead on a diet rich in minimally processed whole foods, including plenty of fiber from fruits, vegetables, legumes, and whole grains, which feed beneficial gut bacteria,” says Chassaing.
Rapozo also emphasizes the importance of eating plenty of fiber to support gut health. “An unbalanced gut microbiome leads to a higher risk of disease,” she says. “But there are things you can do to help.”
