Bonus Post: Emulsifiers in Ultra-processed Foods by Julie Jones

The controversy around ultra-processed food was the topic of a guest post by Julie Jones in June. Shortly after that I received an anonymous comment on the post shown below: 

Congrats for the great articles!
I am from Brazil, where the demonization of ‘ultra-processed food’ has started.
Recently, Dr Monteiro has recorded a video with a famous chef called Rita Lobo (who works with him), saying, between other fallacies, that “Emulsifiers in ultraprocessed foods are detergents. As they are detergents, what we know today is that these emulsifiers take away the protection that we have in the cells in our gut. They take off that layer of fat that protects, which makes a selection of the molecules that get into our blood, into our body. So this can be associated, for example, with allergies. Since there is the passage of molecules that should not pass, they pass due to the emulsifier.”
I am wondering if you could write something about it.

The quotes above were taken from a Google translation of Rito Lobo’s interview of Dr. Carlos Monteiro, the father of the NOVA classification of foods. Contact me for a copy of that translation. Below is a response on emulsifiers in foods from Julie Jones:

two bottles of salsa
Salsas without added emulsifiers

Claims that nearly “all ultra-processed foods contain emulsifiers” and that “emulsifiers are practically detergents” needs to be corrected on several fronts.  First, as noted in earlier blogs the is no legal definition or agreement on what constitutes a ‘processed food’ (PF) or an ultra- processed food (UPF). While NOVA categorizes any food with an additive and any sauce as UPF, many UPFs, including sauces, do not contain emulsifiers. For example, a simple sauce, organic tamari, with only three ingredients -water, organic soybeans and salt – has no added emulsifiers.  In like manner, other sauces – ketchups, barbeque sauces, salsas to name a few – may or may not contain added emulsifiers. Similarly, baked goods such as cookies, crackers, chips, and breads and dairy products such as yogurts and ice cream may or may not have emulsifier additives.

Second, calling emulsifiers ‘detergents’ implies that UPFs carry the same danger as household cleaners. Such language generates unwarranted fear and distrust of foods we eat.  In actuality, the human body produces all kinds of emulsifiers (aka detergents) such as bile acids.  Emulsifiers have a part of the molecule that likes to be in water and a part that likes to be in fat. This enables fat soluble components to be utilized (or in the case of detergents removed from clothing, etc.). Bile acids facilitate digestion of dietary fats by allowing water-soluble enzymes (lipases) to penetrate ingested fat and produce components that can absorbed.

During the breakdown of the most common fats (triglycerides), glycerol and mono- and di-glycerides are formed. Each of these function as emulsifiers or become emulsifiers. In fact, mono- and di-glycerides comprise 75% of the emulsifiers added to food.  When these are found on a food label, they may have names that scare consumers.  For example, succinylated monoglyceride is the combination of succinate, a component produced as carbohydrate breaks down to produce energy, and monoglyceride.  Polyglycerols are several glycerols joined with a common acids such as lactic acid (in dairy) or acetic acid (in vinegar),

Another natural emulsifier is found in every cell membrane -and thus all food- is lecithin. It and related phospholipids allow the transit of both fat soluble and water-soluble components into cells. Lecithin is found in highest amount in egg yolk, but is found in organ and red meats, seafood, eggs, legumes, soy, and green vegetables and oils. It is extracted from soybeans, canola, corn, sunflower seeds, or wheat germ for use food as well as cosmetics and pharmaceuticals.  Limited data show that pharmaceutical doses of these ‘detergents’ may reduce LDL (bad) cholesterol, support the immune system, help promote a healthy lining of the digestive tract, and help prevent mastitis in nursing women. Doses below 5000 mg per are safe unless a person is allergic to the source of the lecithin such as eggs or soy.[1]

A few studies have suggested that the ingestion of a diet high in emulsifiers affects the gut mucous layer and microbiome.  However, the participants ingested 15,000 mg per day.[2]  Ingestion of such high doses from dietary sources is unlikely as the US FDA calculated in 2006 that the total average daily intake was 395 mg/person/day from all emulsifiers.[3]  Even if intakes increased 10-fold in the last 14 years, the dose would be below the 5000 mg/d documented as safe and well below the 15,000 mg/d fed in the study.  Further, it is unlikely that emulsifiers such as lecithin adversely affect the mucous layer as phosphatidyl choline, aka lecithin, is used as a treatment for ulcerative colitis.[4]

Impugning the safety of emulsifiers used in food by calling them ‘detergents’ disregards the thorough testing that these and other additives have undergone. The data have been by teams of experts and health authorities such as those at the FDA and the WHO Joint Expert Committee of on Food Additives.

packages of ranch and red wine vinegar & olive oil salad dressing and cottage cheese
Products containing xanthan gum as an ingredient

Some food additives that are emulsifiers are also sources of dietary fiber. This includes all the gums added to foods such as salad dressings, cottage cheese and baked goods. Dietary fiber intakes in nearly all countries are far below recommended levels. For example, under 4% of Americans meet the recommendations. Fiber has many health functions that have been shown to reduce a number of chronic diseases, improve immune function, and act as prebiotics to help with gut health and the microbiome.[5-8] Some types of fiber such as guar gum or oat bran may help with fullness, a factor very important for those trying to reduce calories.  UPFs with added fiber could help address the fiber gap.

Thus, the presence or absence of an added emulsifier is not a sound reason to choose or avoid a food. Emulsifiers may improve texture and flavor and extend shelf life and reduce rancidity.  This can decrease cost to consumers, impact food safety, and reduce food waste.  All are important at any time.  But during CoVID extended shelf life means fewer shopping trips, and lower cost is important especially for those whose budgets are pressured due to changes forced by CoVID circumstances.

Avoiding foods such as double-fiber whole grain breads, breakfast cereals, yogurts, and frozen spinach souffles because they contain emulsifiers or other additives will do little to improve the nutritional quality of our diets and may actually impair it.  Rather choose foods that will add complete the number of servings needed for each of the food groups to form a healthy and balanced diet.


[1] Leonard, J.  Everything you need to know about lecithin. Medical News Today.  September 5, 2017

[2] Partridge D, Lloyd KA, Rhodes JM, Walker AW, Johnstone AM, Campbell BJ. Food additives: Assessing the impact of exposure to permitted emulsifiers on bowel and metabolic health – introducing the FADiets study. Nutr Bull. 2019 Dec;44(4):329-349. doi: 10.1111/nbu.12408. Epub 2019 Nov 25. PMID: 31866761; PMCID: PMC6899614.

[3] Center for Food Safety and Applied Nutrition US Food and Drug Administration. Guidance for Industry: Estimating Dietary Intake of Substances in Food. FDA series of Guidance documents. 2006

[4] Stremmel W, Hanemann A, Ehehalt R, Karner M, Braun A. Phosphatidylcholine (lecithin) and the mucus layer: Evidence of therapeutic efficacy in ulcerative colitis?. Dig Dis. 2010;28(3):490-496. doi:10.1159/000320407

[5] Veronese N, Solmi M, Caruso MG, et al. Dietary fiber and health outcomes: an umbrella review of systematic reviews and meta-analyses. Am J Clin Nutr. 2018;107(3):436-444. doi:10.1093/ajcn/nqx082

[6] Slavin J. Fiber and prebiotics: mechanisms and health benefits. Nutrients. 2013;5(4):1417-1435. Published 2013 Apr 22. doi:10.3390/nu5041417

[7] Fuller S, Beck E, Salman H, Tapsell L. New Horizons for the Study of Dietary Fiber and Health: A Review. Plant Foods Hum Nutr. 2016;71(1):1-12. doi:10.1007/s11130-016-0529-6

[8] Holscher HD. Dietary fiber and prebiotics and the gastrointestinal microbiota. Gut Microbes. 2017;8(2):172-184. doi:10.1080/19490976.2017.1290756

8 thoughts on “Bonus Post: Emulsifiers in Ultra-processed Foods by Julie Jones

  1. I find much to agree with here.

    Yes, the NOVA groups are squishy. The concept lacks clarity of definition especially for processed food and ultra-processed foods. Personally, I find it more useful to think of NOVA as a continuum rather than as 4 distinct categories.

    Yes, classifying all emulsifiers as intestinal detergents oversimplifies and distorts a complex issue.

    And yes, the presence of an emulsifier is not in and of itself a good reason not to buy a product.

    On the other hand, a healthy amount of skepticism is okay. We humans are complex organisms and it’s seems reasonable to expect there is a lot more to learn. A better understanding of our microbiota as well as how changes in the food matrix effect our digestion and health will come. In the mean time, there’s no harm in noticing how many additives are in a packaged product or placing that product as best we can on a continuous between minimally processed and ultra-processed.


    1. Response to Linn from Julie Jones

      Thanks for the positive comments about my post on NOVA and emulsifiers. As a nutritionist, foodie, and consummate cook (actually I was once a James Beard Judge of cookbooks), I rail against food and nutrition advice that is hard to understand or confusing to consumers. And more importantly may have them make food choices that are less healthy. So, for me, the ‘squishiness’ of the NOVA categories raises huge concerns about its usefulness.

      If NOVA merely were a system that recommended the avoidance of ‘doodles, ding dongs and doughnuts’ and sugar sweetened beverages I would be on-board, but its categorization snares many nutritious foods, even things whole- grain bread, infant formula and alternative (plant-based milks) milks in processed and ultra-processed categories.

      I’ll use two examples to illustrate. First is canned tomatoes. I would argue that canned tomatoes to prepare a delicious chili, pasta sauce or vegetable soup in the dead of winter, especially when access to fresh is either limited by availability or distance, are the better choice. Canned may beat grocery-store ‘fresh’ for the following reasons: 1) in terms of flavor, canned – contrasted with the pink-tinged, pithy, insipid ‘shipped tomatoes – bring more flavor and better texture; 2) in terms of the environment, canned require both fewer shipping miles in atmosphere-controlled trucks or rail cars and BTUs for hothouses; 3) in terms of food waste, along all stages of the supply chain less fruit is lost; and 4) in terms of resources, they generally cost less and can remain in the pantry all winter long.

      NOVA expects the consumer to be able to differentiate NOVA categories among types of canned tomatoes, because they use these distinctions for research associating processed food and ultra-processed food with adverse health outcomes. Under NOVA, tomatoes canned without added salt (rated by New York Times food editors in March as ‘our least favorite’) are deemed ‘minimally processed.’ These, surprisingly, are in the same category as fresh tomatoes. These same tomatoes canned with salt are deemed as ‘processed,’ but canned with more than 5 ingredients or any additives beyond salt such as citric acid, calcium chloride and natural flavors, are deemed ‘ultra-processed.’ So while all the canned tomatoes are processed with identical techniques – in a retort (under pressure) to reach the temperature that ensures their safety, under NOVA a can of tomatoes can be classed as minimally processed, processed and ultra-processed foods. The other ironic thing about the NOVA nutrition advice is that if I use fresh tomatoes or tomatoes canned without salt but I add the ‘processed culinary ingredient’ salt along with other herbs and ingredients to reach more than 5 ingredients of ultraprocessed food, this home prepared food is encouraged despite the fact that it might have more salt than the canned products.

      For the second example, I’ll use bread. Under NOVA a baguette that I bake from processed culinary ingredients, while undoubtedly delicious, has nothing negative attached to its consumption. Also, one from a bakery is deemed as ‘processed’ unless it has more than 5 ingredients or is sold in a plastic bag, then it is ultra-processed. Even a wholewheat baguette with more than five ingredients is ultra-processed and to be avoided. Really? The NOVA categorization purports be based on degree of processing, while it is actually based on factors not related to processing. In actual fact, the mixing, kneading, proofing and baking do not differ, but what makes a bread processed or ultraprocessed is its formulation, defined by NOVA as the number of ingredients; presence of sugar, salt and additives- (even if these are vitamins and minerals that are part of enrichment and fortification efforts); where prepared and by whom; scale; and presence or absence of packaging.

      While overwhelming evidence the world-over associates the intake of whole grain breads and cereals with improved longevity and reduced risk of chronic and other diseases, most whole-grain foods apart from boiled versions or oatmeal, quinoa, bulgur, and brown rice are deemed by NOVA as ultra-processed. Advice to avoid these whole-grain and enriched breads and cereals, in my view, is irresponsible in an era when under 4% of Americans meet the fiber requirement, and fiber intakes worldwide are below recommended levels. B-vitamin enriched grain foods have decreased the number of Americans not meeting the thiamin requirement from 50% to under 10%; and folate-fortified grain products have reduced it from 88% to 11%. More importantly there has been more than a 35% reduction in neural tube defects in the US singe the mandatory fortification of flours.

      I agree that skepticism is healthy for all forms of advice, even from reliable sources or credible experts (it was only after Einstein’s death was one of his ideas proven wrong). Critical thinking is useful in evaluating the methods and results of studies. Questioning is what science does, and this helps us incrementally improve the understanding of our world and improve our health.

      I oppose the NOVA classification because of its confusing categories, squishy definitions, imprecise direction to consumers on what to select to and how to prepare it and combine it with other foods to make a dietary pattern that fits their health and life stage needs and their resources (budget, time available and skill) and ethnic and cultural needs. It can be done with the right mix of foods from all levels of processing.


      1. Hi Linn,

        I concur with what Julie has said. I like your idea of a a continuum, but there will need to be a dramatic reconfiguration of NOVA. I also wonder where sugar comes in in this continuum. There seems to be no problem when using it in the home as a culinary ingredient. When added to a food in a manufacturing facility it becomes the most dangerous ingredient present.


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