How Emulsifiers Impact Your Gut Health
Emulsi-what??? Learn how emulsifiers that are hidden in your food could be impacting your gut health -- and not in a good way…
Irritable bowel syndrome (IBS) is one of the most common gut-brain disorders affecting an estimated 18% of Canadians compared to 11% of the population worldwide (1). The exact cause of IBS remains unknown, but research shows that several factors may be involved in its development: alterations in the gut microbiome, low-grade intestinal inflammation, changes in immune function, disturbed gut motility, miscommunications in the gut-brain axis, psychological stressors, and altered sensations of gut function.
For some individuals, there are questions that remain unanswered…
Why do these changes in the gut microbiome happen in the first place?
What exactly causes the low-grade inflammation, disturbed gut motility, or increased immune responses?
Diet certainly plays an important role.
We know our food plays a significant role in maintaining the health of the gut microbiome. When you consider the harmful effects of the standard Western diet, it’s no wonder that such a large percentage of Canadians suffer from functional gut disorders like IBS and chronic constipation.
Increased consumption of processed foods has Canadians eating more food additives: food colouring, preservatives, artificial sweeteners, and emulsifiers. There is emerging research about the potentially harmful effects of all sorts of food additives, and today we are taking a closer look at emulsifiers and the hidden role they might play in the development of gut issues.
What is an emulsifier?
An emulsifier is a food additive that is used to facilitate processing or to improve the texture and shelf-life of processed foods. Emulsifiers allow for the mixture of two or more substances that would not naturally mix together, such as oil and water. This allows for a smooth, consistent texture. (For example, your Kraft peanut butter or favourite ice cream.)
If you read the ingredients labels of many processed foods, it is not uncommon to find at least one emulsifier. They are commonly found in breads, cakes, baked goods, chocolate, ice cream, dairy product substitutes, coffee creamers and whiteners, margarines, spreads, sauces, salad dressings, canned soups, and candy.
Emulsifiers that are frequently used in modern food production include soy, sunflower, and egg lecithin; mono- and diglycerides; polysorbates; carrageenan; various gums (guar gum, xantham gum, locust bean gum); and celluloses. (For an exhaustive list of emulsifiers approved for use in Canada, click here.)
But first, my disclaimer…
Before we dive in, I want to be transparent: the available research on the effects of emulsifiers on gut health in humans is limited. Most studies to date have been performed on animals or in petri dishes. However, the available evidence is compelling, and it deserves consideration from those who suffer from chronic digestive issues.
What makes your gut “healthy”
In order to understand how emulsifiers impact gut health, it’s important to have a basic understanding of what allows for a healthy gut. Let’s review!
After chewing your food, it enters the stomach where the high acid content and muscle contractions of the stomach wall begin the initial phases of digestion. From here, as the acidic food travels from your stomach to your alkaline small intestine, it triggers the release of bile from your gall bladder and digestive enzymes from your pancreas. This continues the digestive process and allows for the absorption of nutrients into the bloodstream.
Wave-like contractions of the small intestine propel food along until it reaches the colon. The far end of the small intestine, along with the entire colon, house the majority of your good gut bugs, often referred as the gut microbiota or microbiome.
The microbiome is one of three parts that make up your gut barrier. More than 100 trillion microbes live here with approximately 1,000 different bacterial species (2).
These microbes are key players in your gut barrier’s main functions: preventing infection from outside invaders; processing and detoxifying chemicals from food; regulating your body’s metabolism; and, in a healthy individual, helping to regulate inflammation.2
Your microbiome also helps to digest food components that your body cannot handle on its own, such as tough plant fibers, through a process of fermentation. Byproducts of this process, called short-chain fatty acids, aid in the overall maintenance and health of the gut.
The other components of your gut barrier include the mucus layer that protects the very thin lining of the gut wall, known as the epithelial lining.
The gut wall is only one cell thick and the spaces between each of the cells (called “tight junctions”) allow for the passage of nutrients from the intestines into the blood stream. The ability of substances to pass through these spaces is referred to as intestinal permeability. Increased intestinal permeability leads to problems with immune function, inflammation, and overall poor digestive health.
To sum up: if your gut barrier is not in a healthy state, illness easily follows.
How emulsifiers could affect your gut health
1. Decreased diversity in the microbiome
Diversity in the microbiome (meaning: lots of different species of bacteria) is a significant indicator of human health. Fecal samples of patients with IBS have shown lower microbiome diversity (3).
Two animal studies that looked at mice fed a diet that included the emulsifiers polysorbate 80 (P80) and carboxymethylcellulose (CMC) showed a reduction in microbiome diversity in the mice fed the emulsifier-diet compared to controls (4).
2. Changes in the composition of the microbiome
Some emulsifiers change the genes of harmful bacteria. These changes allow them greater agility to move about in the intestinal tract, and as a result, give them greater ability to cross the gut wall barrier (4). This could trigger inflammatory pathways through the activation of the immune system in response to these foreign invaders.
3. Low-grade inflammation
Low-grade intestinal inflammation has been implicated in IBS. When the microbiome and mucus layer are exposed to emulsifiers within the intestinal tract, it can lead to changes in the microbiome that decrease diversity and increase the population of microbes that cause inflammation (4).
Animal and in vitro studies that looked at different emulsifiers including P80, CMC, carrageenan, guar gum, xantham gum, and locust bean gum demonstrated negative impacts on the number and composition of the microbiome, including more inflammatory species and fewer anti-inflammatory microbes (5, 6).
4. Decreased thickness of the mucus layer
A thinned mucosal layer allows for easier passage of bacteria through the gut barrier where they can enter the body systemically. This can trigger an immune response and subsequent inflammation.
Emulsifier interaction with the microbiome has been shown to cause a thinning of the mucus layer (4). This leads to decreased gut barrier integrity and increases susceptibility to not-so-friendly microbes.
5. Increased intestinal permeability
As mentioned, increased intestinal permeability allows for the easier passage of bacteria and proteins from food through the gut wall. This could potentially activate an immune response leading to gut symptoms often associated with IBS. Immune responses to frequently consumed foods can lead to the development of food sensitivities if the gut barrier is not intact.
Emulsifiers, such as carrageenan, have been shown to increase intestinal permeability in both rats and guinea-pigs (4).
Several studies demonstrated increased intestinal permeability, microbiome changes, and decreased mucus production in mice fed CMC, leading to increased inflammation. Similar results were found in mice fed P80 (7).
A final word…
Although more studies are needed to fully understand the impacts of emulsifiers on human gut function, the evidence from animal and in vitro studies is compelling.
We now know that alterations in the gut microbiome, increased intestinal permeability, activated immune response, and inflammation play a role in the development and preservation of IBS symptoms.
For individuals looking for a way to improve their gut health, it may be worth reducing your consumption of processed foods that emulsifiers to see if there is any improvement in symptoms.
After all, we can begin to change our gut microbiota within a matter of 3 days with dietary interventions alone, and the cells that line the gut wall turn over every 3 to 7 days.
References
1. Canadian Digestive Health Foundation, IBS, statistics - https://cdhf.ca/digestive-disorders/irritable-bowel-syndrome-ibs/statistics/
2. The Mind-Gut Connection by Emeran Mayer, MD
3. Food Additives, Gut Microbiota, and Irritable Bowel Syndrome: A Hidden Track -https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7730902/
4. Food Additive Emulsifiers and Their Impact on Gut Microbiome, Permeability, and Inflammation: Mechanistic Insights in Inflammatory Bowel Disease - https://academic.oup.com/ecco-jcc/article/15/6/1068/6041235
5. Food additives: Assessing the impact of exposure to permitted emulsifiers on bowel and metabolic health – introducing the FADiets study (2019 Nov 25) - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6899614/
6. Direct impact of commonly used dietary emulsifiers on human gut microbiota -
https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-020-00996-6#Tab1
7. Food Additives, a Key Environmental Factor in the Development of IBD through Gut Dysbiosis - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8780106/
8. List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (Lists of Permitted Food Additives) - https://www.canada.ca/en/health-canada/services/food-nutrition/food-safety/food-additives/lists-permitted/4-emulsifying-gelling-stabilizing-thickening-agents.html
