Emulsifiers in food linked to inflammation, anxiety and depression
When you eat processed foods, you’re not only being exposed to unhealthy ingredients like high-fructose corn syrup and synthetic fats but also the additives used to create a uniform, shelf-stable product. Emulsifiers, including carboxymethylcellulose (CMC) and polysorbate 80 (P80), are among them, and research suggests they could be leading to inflammation, anxiety and depression in those who consume them.
If you’ve ever made salad dressing or mayonnaise at home, you’re probably aware that the ingredients naturally separate, as oil and water don’t mix. Yet, salad dressings and mayonnaise that’s store-bought stays mixed. This is due to emulsifiers, which blend otherwise unblendable ingredients while also reducing stickiness, controlling crystallization and preventing separation.1
Their benefit to the food industry is obvious, but once in your body they could be wreaking havoc on the microbes in your intestines, leading to metabolic problems and even affecting your brain.
Food Emulsifiers May Affect Brain and Behavior
Because your gut and brain communicate via your gut-brain axis, altering microbes in your gut can influence anxiety and behavior, leading researchers to speculate that consuming emulsifiers may also influence mental health and behavior. Indeed, the mice study confirmed that exposure to emulsifiers led to chronic intestinal inflammation, obesity and altered gut microbiota composition in mice.
“Importantly, emulsifier treatment altered anxiety-like behaviors in males and reduced social behavior in females. It also changed expression of neuropeptides implicated in the modulation of feeding as well as social and anxiety-related behaviors,” researchers wrote in Scientific Reports.3
In short, these commonly used food additives led to changes in microbiota, physiology and behavior in the mice, and it’s possible similar effects could occur in humans. The study authors concluded:4
“[O]ur data support the general notion that some cases of behavioral disorders may have been impacted by exposure to modern chemical stressors and, more specifically, that synthetic dietary emulsifiers may be one such stressor.”
Food Emulsifiers Could Be Messing With Your Gut, Leading to Metabolic Disease
In 2015, it was previously found that low concentrations of emulsifiers (CMC and P80) induced low-grade inflammation, obesity and metabolic syndrome in mice.5 How this occurs could be due to the detergent-like nature of the chemicals, which could disrupt the interactions between mucus structures that cover the intestinal surface and bacteria.
The mucus barrier keeps gut bacteria away from epithelial cells that line the intestine, but disrupting this could lead to gut inflammation and associated diseases. Researchers even suggested that emulsifiers could be promoting the increase in inflammatory bowel disease (IBD), an autoimmune condition that involves inflammation in your digestive tract and includes both Crohn’s disease and ulcerative colitis, seen in recent decades.6
The emulsifiers caused chronic colitis in mice with already abnormal immune systems, while in mice with healthy immune function, they resulted in mild intestinal inflammation and subsequent metabolic dysfunction that led to obesity, hyperglycemia and insulin resistance.
The emulsifiers were fed at levels that an average person would be exposed to if eating a lot of processed foods, suggesting these additives may indeed affect the health of many Americans. Further research also found that exposure to CMC and P80 alters the structure and transport properties of intestinal mucus, which could affect interactions between intestinal lumen contents, microbes and underlying tissue, contributing to inflammation.7
Emulsifiers may also alter the functional characteristics of gut microbiota, for instance increasing the expression of flagellin (a protein), which in turn increases the ability of bacteria to penetrate the mucus barrier.8
Carrageenan, Another Popular Emulsifier, Linked to Health Risks
Carrageenan, an emulsifier extracted from red seaweed, is also commonly added as a thickening agent to processed foods. It’s another food additive you should be aware of as, like CMC and P80, it’s linked to inflammation and other health risks.
The International Agency for Research on Cancer (IARC) classifies degraded carrageenan as a possible human carcinogen. Degraded carrageenan, which is processed with acid instead of alkali (as the food-grade carrageenan is) is so inflammatory that it’s used in laboratory studies to induce inflammation in animals to test anti-inflammatory agents.
While food-grade carrageenan is a different product, there’s concern that stomach acid could essentially turn food-grade carrageenan into potentially carcinogenic degraded carrageenan once inside the body.9
Further, exposure to even undegraded (i.e., food-grade) carrageenan has been linked with an increased occurrence of intestinal ulcerations and, potentially, cancer growths.10 In a 2016 report by The Cornucopia Institute, the health risks of carrageenan were further revealed, with a slew of studies raising serious concerns over carrageenan’s inflammatory properties.11
Why Inflammation-Triggering Emulsifiers Could Contribute to Depression
Emulsifiers trigger chronic, low-grade inflammation in your body, to which depression is strongly linked. Not only are elevated biomarkers of inflammation commonly found in people with depression, but stimulating inflammation has also been shown to trigger depressive symptoms.
It’s believed that inflammatory cytokines in your body interact with multiple pathways involved in depression, including neuroendocrine function and mood regulation.12 “Depression and inflammation fuel one another,” researchers wrote in the American Journal of Psychiatry, adding that in the case of inflammation, “depression fans the flames and feasts on the heat.”13
“Inflammation plays a key role in depression’s pathogenesis for a subset of depressed individuals; depression also primes larger cytokine responses to stressors and pathogens that do not appear to habituate,” they said. Edward Bullmore, head of the psychiatry department at the University of Cambridge, estimates about one-third of patients with depression are affected by an inflammatory component.
Bullmore is the author of a book, “The Inflamed Mind: A Radical New Approach to Depression,” which reveals the importance of inflammation in the development of depression.
He told CBS News, “We’ve known for a long time there’s an association. Inflammation and depression go together. If you have arthritis, psoriasis, inflammatory bowel disease, for example, all inflammatory diseases in the body, your risk of depression is going to be much increased. The new understanding is that that association could be causal. It’s not just a coincidence.”14
During inflammatory states, brain cells called microglia are activated. When this happens, an enzyme called indoleamine 2,3-dioxygenase (IDO) directs tryptophan away from the production of serotonin and melatonin, instructing it instead to produce an NMDA (an amino acid derivative) agonist called quinolinic acid, which can trigger anxiety and agitation.15
There are many sources of inflammation in the modern world, from diet and pollution to emotional stress, and emulsifiers in processed foods likely only add to the problem. If you suffer from depression, it may be well worth your effort to take steps to reduce the level of inflammation in your body, starting with the elimination of processed foods, a common source of exposure to emulsifiers and other inflammatory agents.
Where Are Emulsifiers Found?
In addition to carboxymethylcellulose, polysorbate 80 and carrageenan, similar emulsifiers include lecithin and xanthan gum. Mono? and diglycerides of fatty acids, stearoyl lactylates, sucrose esters and polyglycerol polyricinoleate are also commonly used emulsifiers, widely used in processed foods in order to:16
- Enhance the appearance of foods by keeping them from separating or showing other signs of instability
- Enhance shelf life
- Improve the food’s taste, color, odor and mouthfeel
- Encapsulate unpleasant aroma
- Produce low-fat foods that have the same mouthfeel as their full-fat alternatives
If you consume processed foods, you’re probably consuming emulsifiers, but they’re most commonly found in the following foods:17
- Baked goods, including bread, biscuits and cakesFat-based spreads, such as margarine, nut butters and shortening
- Ice cream and other dairy dessertsVeggie burgers and hamburger patties
- Salad dressing and mayonnaiseCandy, including caramels, toffees, gummies, chocolate and lollipops
- Beverages, including soft drinks, wine and cream-based liqueursNondairy milk
Concerns surrounding emulsifiers are increasingly valid, since no one knows the amount of emulsifiers actually ingested by the average person. Many emulsifiers are used alongside other emulsifying agents, and there could be synergistic or enhanced health effects when consumed in this manner.
Further, certain additives, including CMC and carrageenan, are not thought to be metabolized, which means they could potentially affect the entire gastrointestinal tract.18 While many animal studies have been conducted into the safety (or lack thereof) of emulsifiers, little is definitely known about their potential for toxicity.
“Most emulsifiers and thickeners have no defined level of toxicity, because the highest dose required to produce an adverse effect is above the level experimental animals can reasonably consume,” according to a study in Alimentary Pharmacology & Therapeutics.19
How to Avoid Emulsifiers in Your Diet
To avoid emulsifiers in processed foods, you’ll want to read labels and look for the following emulsifying additives:
- CarboxymethylcellulosePolysorbate 80
- Xanthan gumMono- and diglycerides of fatty acids
- Stearoyl lactylatesSucrose esters
- Polyglycerol polyricinoleate
However, it’s important to understand that foods may contain emulsifiers that aren’t listed on the label if they make up less than 5 percent of the final product and do not provide a “technological function.”
“An example of this is the case of … citrus soft drinks that use stabilizers as a weighting agent,” researchers explained. “Indeed, many citrus soft drinks do not have additive stabilizers listed on their ingredients lists, yet the flavor remains stable and evenly dispersed through the bottle.”20
Even choosing organic isn’t a guarantee that you’re avoiding emulsifiers. Organic watchdog groups such as The Cornucopia Institute have called for carrageenan to be removed from the U.S. list of approved organic ingredients.
In December 2016, the National Organic Standards Board (NOSB), the U.S. Department of Agriculture’s (USDA) expert advisory board, voted to do just that. After hearing evidence on the potential health risks and the availability of alternative ingredients, NOSB voted to remove carrageenan from the organic ingredients list.
In April 2018, however, the USDA overruled NOSB’s advice and reapproved carrageenan for organic foods. The Cornucopia Institute has also created a shopping guide to avoiding organic foods with carrageenan, which can help you choose wisely. But your best bet to avoid these additives in your food is to read ingredient labels diligently — and choose whole, unprocessed foods as much as possible.