How Emulsifiers Are Messing with Our Guts (and Making Us Fat) | Civil Eats

How Emulsifiers Are Messing with Our Guts (and Making Us Fat)

Common food ingredients like polysorbate 80, lecithin, and carrageenan interfere with microbes in the gastrointestinal tract, says new study.

Update: On April 4, 2018, the USDA updated the Federal Register to allow carrageenan to be included in organic food, despite the National Organic Standards Board’s earlier vote to ban carrageenan.

Scan the fine print on almost any processed food in the grocery store and you’re likely to find emulsifiers: Ingredients such as polysorbate 80, lecithin, carrageenan, polyglycerols, and xanthan and other “gums,” all of which keep ingredientsoften oils and fatsfrom separating. They are also used to improve the texture and shelf-life of many foods found in supermarkets, from ice cream and baked goods, to salad dressings, veggie burgers, non-dairy milks, and hamburger patties.

Now, a new study released today in the journal Nature suggests these ingredients may also be contributing to the rising incidence of obesity, metabolic syndrome, and inflammatory bowel disease by interfering with microbes in the gastrointestinal tract, known asgut microbio.”

This news may surprise consumers, given the fact that emulsifiers are approved for use by the U.S. Food and Drug Administration (FDA), and appear in many foods otherwise considered “healthy,” including some in which their presence helps to reduce transfats and gluten, and many labeled organic and non-GMO.

“What we’ve been attempting to understand for the past several years is the increase in metabolic syndrome and inflammatory bowel diseases” that affect digestion, explains Andrew Gewirtz, Georgia State University professor of biology and lead study author. Metabolic syndrome includes obesity, increased risk for Type 2 diabetes, and cardiovascular diseases like heart attacks and strokes. All these conditions, Gewirtz explains, “are associated with changes in gut bacteria.

The recent, dramatic increase in metabolic-related diseases cannot be attributed solely to genetics, says Gewirtz. Human genetics haven’t changed in recent decades. So he and his colleagues set out to investigate environmental factors that might be responsible, including “modern additions to the food supply.”

Previous research suggested that emulsifiers could be implicated. So for the new study, researchers fed mice emulsifiers through water or food. The experiment used polysorbate 80 (common in ice cream) and carboxymethylcellulose, and found that it altered microbiota in a way that caused chronic inflammation. They tested the emulsifiers at levels below those approved for use in food and also at levels modeled to mirror what a person would eat, if they eat a lot of processed food.”

Mice with abnormal immune systems fed emulsifiers developed chronic colitis. Those with normal immune systems developed mild intestinal inflammation and a metabolic disorder that caused them to eat more, and become obese, hyperglycemic, and insulin resistant.

The inflammatory response prompted by eating emulsifiers, explains Gewirtz, appears to interfere with “satiety”–the term scientists use for behaving like you’ve eaten enough–and can lead to overeating. Mice experiencing this inflammation therefore developed more fat. “There’s a chain of events,” says Gewirtz.

We’ll bring the news to you.

Get the weekly Civil Eats newsletter, delivered to your inbox.

Gewirtz explains that the emulsifiers appear to disturb both the bacteria normally present in the gut and the gut’s protective mucus layer. Something in the chemistry of the emulsifiers seems to change the microbiota and how these bacteria interact with the intestine itself. The combination, Gewirtz says, sets the stage for inflammation.

Gewirtz is quick to say that these food additives are by no means the “only cause of the obesity epidemic or inflammatory bowel disease.” But emulsifiers may be a factor contributing to excess eating.

He also points to the fact that emulsifiers are “very common” food additives and their increased use in the food supply “roughly parallels the increase in these chronic diseases.”

That emulsifiers appear to be associated with metabolic and digestive problems and are used in some reduced-fat, dairy- and gluten-free products that consumers may be choosing for health reasons, prompts additional questions. Next, the scientists plan to test additional emulsifiers and to follow up with tests in people.

Another important point, says Gerwitz, is that theseand many otherfood additives are inadequately tested by the FDA. A 2013 study found that almost 80 percent of the chemicals the agency allows in food lack testing information that would help the FDA estimate the amount people can safely eat.

Maricel Maffini, who co-authored the 2013 study, suggests the FDA’s current system of approving food additives could be improved by requiring additive safety to be reviewed periodically and by basing safety information on how much people actually eat. With additives like emulsifiers in so many different foods, some people may be eating far more than the FDA estimates, says Maffini.

Thank you for being a loyal reader.

We rely on you. Become a member today to read unlimited stories.

Gewirtz and colleagues also note that the FDA classifies some food additives­including various emulsifiers­as Generally Regarded as Safe (GRAS), meaning they are not subject to FDA “premarket” review. The upshot is that FDA oversight may not be keeping up with the latest science, adding to shoppers’ existing confusion about what appears on ingredient lists.

According to Marion Nestle, NYU professor of nutrition and food studies, this study “suggests that artificial emulsifying agents may not be harmless and that their use should be scrutinized carefully.


Elizabeth Grossman was a senior reporter for Civil Eats from 2014 to 2017, where she focused on environmental and science issues. She is the author of Chasing Molecules, High Tech Trash, Watershed and other books. Her work appeared in a variety of publications, including National Geographic News, The Guardian, The Intercept, Scientific American, Environmental Health Perspectives, Yale e360, Ensia, High Country News, The Washington Post, Salon, The Nation, and Mother Jones. She passed away in July 2017, leaving behind a legacy of dedication to her mission of journalism that supports and protects people and the planet. Read more >

Like the story?
Join the conversation.

  1. Deborah Carasso
    The FDA has to get on the ball. The people on Gluten Free are often on it for a reason and I, personally, do not appreciate there being poisonous things in the foods we have to eat and that these may be making our conditions worse, not better.
  2. Felix
    Please leave gluten out of this discussion. People who can't eat gluten have celiac disease. It is a T-cell mediated immune reaction to gliadin and it has nothing to do with what this article is talking about. People who are gluten-free because it's trendy are essentially making it difficult for people to procure gluten-free foods.

    I do agree with you about the FDA getting on top of it. The only issue is, the FDA doesn't really do much on a national level.
    • Rick Clarke
      What we NEED is to find out just why the FDA is approving products we ingest that harm us. I have had Crohns disease for 45 years and I have avoided many foods over the years and now my doc wants to put me on HUMIRA. That will NOT be happening. Food additives ARE the problem and probably have contributed to further health complications not better health.
  3. wikiBuddha
    FDA should be renamed "Food and Drug Advisory". They should simply offer advise on food and consumption. They should have information on effectiveness, addiction and history of drug use/abuse. We should be able to use this information to make decisions. They shouldn't be creating laws based on their (often faulty) research, that clearly violates the 4th amendment (I'm secure in my person. I don't need some agency declaring what I can put into my body). I still don't understand why people who have so little control over themselves seek so strongly to control others.
  4. Dr Bunsen Honeydew
    Is this what's been giving me gas for so long? [Not being funny]
  5. Brian
    What do we look for on a nutrition label to avoid emulsifiers? How does my infant son, who is genetically vulnerable to Crohn's Disease, avoid triggering it with environmental factors as he grows up?
  6. Elizabeth Grossman
    Here's a list of emulsifiers allowed in food from Health Canada to get you started. There are also various European lists you can find with a simple web search. FDA does not sort its food additives list this way. You'll also find lists from companies that make these food additive products but what appears on the label may vary, I think, from names under which the additives are sold to food manufacturing companies. Wish it was easier to find a comprehensive list. URL below
  7. Brian, I'm sorry to hear about your son.The best way to avoid label confusion is to stop buying fo to start od-like substances (the stuff with labels) -- and to start feeding your son real food only.

    I stopped eating processed food (and sugar) 8 years ago. I make everything I eat in my own kitchen, including sourdough bread, bagels, every meal and even the dog's treats (peanut butter molasses). During that time I've gone from 245 to 132 pounds, and I'm healthier than ever.

    Thanks for the great article.
  8. Yogi Greg
    THE FDA APPROVES ANYTHING A BIG CORP comes to them with as long as they "bring a big, fat check with them." Your health and well-being has been off their radar-screen for a couple of decades...
    • Rick Clarke
      I truly believe that as well.
  9. Cat
    Yet another arguement for the soundness of the "whole foods" movement. If you cook from scratch, or at least try to start with single ingrediant foods, you won't be ingesting all these potentially harmful artificial emsulsifiers!
  10. Diane
    Please note that chocolate has been diluted by the emulsifying polymer PolyGlycol Poly Rincolate. PGPG is also GRAS-generally recognized as safe.
  11. Cat
    Just how does "People who are gluten-free because it’s trendy" actually make it "difficult for people to procure gluten-free foods"?!? I'd say the reverse is true -- gluten-free options are now more widely available than ever!
  12. Ray
    This doesn't happen in Europe. We need stricter regulations for the health and safety of the public not more means for greed driven corporations to extend shelf life and increase profits at the expense of public wellness.
  13. Dena
    Just weighing in on the gluten free conversation. I do not have celiac disease and I don't care about trendy.... I have fibromyalgia and have spent 20 years trying to find some relief. I accidentally discovered a Gluten free diet reduced my daily pain level from 5-6 down to 2 or less! It is amazing and unexpected. And yes, the day after I eat gluten I see it in the swelling around my knuckles and wrist. I am thrilled for such a simple solution after all these years!
  14. Ray
    fyi "wikiBuddha" science backs it up so the practice of
    overuse of emulisifers for profits needs regulation to stop its use. Why should I have to scrutinize every label
    For crap ingredients that shouldn't be in there in the
    First place! They will just keep going until it's something
    That resembles food but..... And the concern of that
    company stays on the almighty dollar. Unsafe and uncivilized!
  15. Correlation does not equal causality.
    Extremely frustrating to see the demon du jour, especially when one has food allergies and must rely on substitutes that almost always include things like carageenan.
  16. David Brugge
    Back off a bit from the manufacturers pushing emulsifiers for their greedy profits. First and foremost, the emulsifiers are there because we the public have been demanding them. I like my food products to not separate in the jar, I like the mouth feel of my ice cream, I want my chocolate to resist turning white and chalky when it has been warm. Everyone wants better, more flavorful, more enjoyable foods.
    We have trusted the FDA to test food additives and keep us safe. They have let us down. They have been influenced by business to dampen their concerns about product safety.
    And when will this change? Only when we, the public demand a change. Articles such as this goes a long way in stirring a passionate and informed electorate.
  17. John Firth
    Lecithin is found in eggs, milk and other natural foods. Egg yolks are used in cooking as an emulsifier.
    Lecithin appears to have some health benefits so I won't be avoiding it. But I don't eat processed food so will be avoiding other additives
  18. The study referenced above was specific to CMC and Polysorbate-80 yet the author has worded this article in such a way as to lead people to believe it also covers carrageenan and xanthan.
  19. This research and others like it only confirms my position that consumers need to hold the big food companies responsible and demand that they stop adding all of these unnecessary chemicals and additives to our food. When you make food from scratch at home do you do not add emulsifiers to the mixture? Of course not. I do not subscribe to the argument that they are needed to keep the food from separating. Most foods do not stay on the shelves or freezers long enough to separate. The FDA is a joke. I do not respect the agency nor do I depend on their recommendations, they work for the BIG FOOD companies not the citizens of the US.
  20. Christine
    You can have gluten sensitivity (along with other food sensitivities and intolerances) that stem from intestinal imbalance and it has nothing to do with being trendy. Beware of the black/white, all or nothing judgements. I would give anything to be able to enjoy gluten foods without worrying about the fall out. I certainly am not looking to usurp a true medical disease, but I am also not faking it. I hope to work my way back to being able to eat it again, but in the meantime, the intolerance is very real. That said, carrageenan was one of the first to go. Problem is, as you are trying to make your way back from disorder, a lot of "health" foods are full of emulsifiers. Best to get off packaged products altogether and eat mostly whole foods
  21. TT
    Concluding that all emulsifiers are bad like these two very artificial sounding ones seems premature, no?
  22. Less expensive and better for you: eat whole organic veggies and fruit, whole organic grains, seeds, nuts, legumes, eggs, grass-fed meat and dairy. You might be surprised how easy and delicious this way of nourishing your body becomes, once you get used to it! I walk down the "twinkies" aisle in grocery stores and am not the slightest bit tempted!
  23. julie
    I have an auto-immune thyroid disease and as a result am gluten intolerant. I found that when I tried gluten free packaged foods, my symptoms were just as bad and sometimes worse than when eating gluten. I came to the conclusion on my own that it was the emulsifiers and have been steering clear of them as much as possible. So glad to see this article showing that really is the case. I believe these same emulsifiers are also used in a lot of prescription medications which I also have problems with. Would love to see the FDA disallow them!
  24. Honey
    Natural organic honey helps gut bacteria.
  25. Telula
    I also have very severe fibromyalgia and other associated conditions including food intolerances (gluten, dairy, etc). And while I am trying to work my way to even healthier eating than what I already do, I just don't have the physical energy or ability to make my own meals all the time, and if we are taking emulsifiers I would have to make my own almond milk (not easy on my muscles and starts tasting off a few days after making, so then another round comes in) and many other items. So making all our own food from whole food items isn't an option for everyone, especially those of us with illnesses, busy families or jobs, or any combination of the three. And we have to rely on premade food items like organic frozen meals or almond milk etc
  26. I have Celiac disease and read all the labels.
  27. Geri
    If everyone ate fresh prepared foods we would know what is in it!
  28. Linda
    Yep, Telula. It's hard to make your own food from raw ingredients AND be able to eat a nutritiously varied diet to avoid malnutrition. I try, even going so far as to grow much of it myself, but it's not as easy as "just eat whole foods!" I find myself relying on lots of "easy" things on days when I'm just too busy to cook - boiled eggs from the fridge, nuts, cheese. Yes, it'd be better if I always ate something I cooked, but when I'm just home from work and just back inside from doing chores outside, it's awful hard to then go to the garden, pick some kale, and fry up something fresh and good. I'm not giving up! But I agree - it's harder to eat well and safely than some make it out to be, and it shouldn't be that way.
  29. Madfortulips
    Great article. Toss the packaged food..skip the chemical ice cream..make your own! It doesn't happen over night, it takes work to eat more simply..seems crazy, right? But once you do, you get a rhythm to it all and a sense of well being knowing what exactly you are eating. And no I'm not perfect, but we each need to take responsibility for what we put in our mouths. Stayed in Europe last year and they have tiny kitchens and shop every day for fresh meat, veg., junk food around the house, pantry filled to the brim, or over stuffed refrigerators. They eat well but simply and take lots of time doing it..seems much healthier to me. Side note: for gums if you are baking...
  30. Leslie
    Great article. I notice less guar gum on labels, thanks as I have an anaphylactic reaction to Guar gum;. Now they use zanthan gum and other things. Yikes. What was wrong with the old fashioned natural recipe? Stuff is flying off the shelf, who should be worried about a need for stuff like gums and etc? OK then the gut issue. Mine is messed up now, and I have been very careful most of my life about staying away from threatening additives. Guess it is the GMO wheats that make the breads we were eating. Something changed my genes...think it was GMO's. Gut is pretty confused, unable to process many foods. Would not wish this on any child...or adult. Hope to get it figured out soon. Stuck with it for life if not.
  31. denise
    just don't eat processed foods. so simple
    • James Guecia
      I went out to have dinner at Olive Garden tonight. I always question the staff and management in regards to emulsifiers. They where unable to offer any foods free of all emulsifiers. Eating out is not easy at all.
  32. Weighing in on the gluten-free diet part, and it is relevant to this discussion. Celiacs don't own "gluten-free." I'm highly gluten sensitive and suffered from an immediate outbreak of eczema on my ear that lasted six months after eating lentil and barley soup. I'd been gluten-free for a year at that point. Also, the "gluten-free" products usually have xantham gum in them. It's better to find a paleo recipe for sweets that won't contain those additives than to buy those gluten- free cookies and cupcakes at the store.
  33. MoodyFoodie
    @Ray "This doesn't happen in Europe." Most if not all the emulsifiers discussed in this article are also authorized and used in Europe. This is new science re. their possible effects on gut health and obesity. Despite what people will tell you the European diet is not all people shopping everyday for fresh foods from their local markets, but processed foods from large retailers like in the US, and - obesity is also growing! So this is as much a concern to you in Europe as in the US.
    Also this is not just about Gluten-free....
  34. Jamie
    I really appreciate this information and realize for myself the import of whole, real foods. It seems silly to have to (re)learn this now at 50+ years old. I've lived so far removed from the basics of good whole real foods, while trying to maintain the typical fast-paced life--ugh. Recipe for obesity and lack of well-being. I'm feeling re-inspired today to get back to the fresh local colorful and varied foods my organism is truly best suited to. Thanks.
  35. "This news may surprise consumers, given the fact that emulsifiers are approved for use by the U.S. Food and Drug Administration," .... Nope, nothing surprises me, countries like China have bans on certain foods that they are allowed to sell to America, but dont allow their citizens to endanger themselves from ingesting them.
  36. sonja
    Grest article, never knew the significance before, a friend told me to use a good coconut milk without emulsifier, now I know why, thanks
  37. Thank you for a most enlightening article and explanations regarding 'Emulsifiers' in foods.
    I have been 'ill' for years with bowel related problems and this had resulted in my losing quite a few jobs over the years. This has been mostly because employers do not understand the downside of having IBS and refer to it as 'your little toilet problem'. The words alone could start me off! I will spending hours shopping now reading all the packets.
    Thanks again
  38. Kay
    As a vegan, I use almond milk & creamer, both of which use some of these products. Do have any alternatives without them?
  39. Shara Marberry
    Thank-you so very much for your research and the information given in this article. I am one that is truly concerned and feed up with the FDA's
    lack of knowledge or their decision not acknowledge these findings. I feel it is at utmost importance to our health to get these questionable additives out of our foods , TOTALLY. Thank-you again for this article and please keep up the good work.
    • James Bailey
      It's not ignorance it's neglect. The FDA approves whatever has the most generous lobbyist.
  40. Carolee Brady
    So if I use liquid lecithin in my morning protein shake is that good or bad for me .
    It's a emulsifier and your article I just read seamed to me might not be good for me and a weight gainer
  41. Patricia Cremer
    Thank you for this. I try and tell everyone and I get the so what attitude and this I am sending to some,

    Again thank you
  42. James Bailey
    I believe the FDA needs to be held accountable for so much mislead information to the public for the sake of profits. Perhaps another agency should be established to govern the motives and actions of the FDA.
  43. philippa aplin
    I have just realised that emulsifiers have been the cause of my extreme digestive issues. I have actually begun writing a blog about it as I feel that many people are mistakenly under the impression that they must be gluten intolerant when they are actually just affected by emulsifiers in food and more so from gluten free foods. I figured it out myself after years of mis-steps but many won't and will un-needingly take on extreme diets such as FODMAPPING for no reason. My blog can be found at
    I am not selling anything or trying to be famous. i just want to help others have a normal digestive system.
  44. Rick Clarke
    Probably a lawsuit is all that "THEY" would understand.
  45. Barbara Patchin
    Thank you for all this information. I have been reading all labels and found that what you have found is true. But do you know that there is many more chemical ingredients than the ones you have found that are very dangerous and is causing death to all of the people. I believe it is time to fight this.
    Why is it that when people found out that this was what they were putting in dog food they fought tooth and nail to have it removed yet people are dying from these chemicals and no one cares enough to stop it. Are dogs lives more important than people?
  46. This explains a lot. Mice with abnormal immune systems fed emulsifiers developed chronic colitis. Those with normal immune systems developed mild intestinal inflammation and a metabolic disorder that caused them to eat more, and become obese, hyperglycemic, and insulin resistant. Apart from being a mouse this is me. Ive a probelm with immunity and i get all thay follows also been tested for celiac disease which is negative but i do have to avois a lot of processed foods like bread biscuits cake some wines breakfast cereals. I didnt know what my intolerance is to until ive read this so thank you. Im going cut all processed food out now and see how it goes fingers crossed.
  47. Diane Shelford
    I have been eating gluten free food for 7 months, as a result of gastro-intestinal problems. Since coming off gluten this has resolved but I had noticed I was getting weaker and a whole host of other issues. When I decided to stop buying processed food I became stronger, healthier and with far more energy. I feel amazing but am seriously worried about people's lack of knowledge about what they are eating. I only crave healthy food now. I had a healthy lifestyle before but wasn't getting the nutrients for whatever reason still to be pinpointed by me. Not much trust in doctors so have self diagnosed.
  48. James Guecia
    Until recently I suffered from Crohn's disease. Since hearing a podcast on NPR I began reading food labels being careful not to purchase items that contained Carrageenam and other emulsiers. I no longer suffer from Crohn's disease. Unfortunately because of years of treatment with steroids I now suffer many other ailments. Thank you for your research. Please continue to get the word out.

More from



Restaurants Create a Mound of Plastic Waste. Some Are Working to Fix That.

A small but growing number of restaurants are moving away from single-use plastic take-out containers, which usually end up in the trash because they can’t be recycled. 


Mayor Eric Adams Scrapped NYC’s Compost Project. Here’s What Will Be Lost.

Hands holding compost in new york city. (Photo credit: Angelica Ang)

Nik Sharma Offers His Top Tips for Home Cooks to Fight Recipe Fatigue

Nik Sharma baking at left, and tossing a chickpea dish at right. (Photo credit: Nik Sharma)

A Guide to Climate-Conscious Grocery Shopping

Changing How We Farm Might Protect Wild Mammals—and Fight Climate Change

A red fox in a Connecticut farm field. (Photo credit: Robert Winkler, Getty Images)