Low Emulsifier Diet for Crohn's Disease: ADDapt Trial Results

If you have ever flipped over a package of ice cream, salad dressing, or sliced bread and wondered what all those E-numbers actually do inside your body, you are not alone. For those of us living with Crohn's disease, that question carries extra weight. A growing body of research suggests that emulsifiers - the additives that keep processed foods smooth, stable, and shelf-ready - may be quietly fueling the kind of gut inflammation we know all too well. And now, the largest dietary randomized controlled trial ever conducted in Crohn's disease has put a low emulsifier diet for Crohn's disease to a rigorous test, with results that deserve a close look.

The ADDapt trial, presented at the 2025 European Crohn's and Colitis Organisation (ECCO) Congress, enrolled 154 patients across 19 UK hospitals and found that cutting back on emulsifiers led to meaningful improvements in both symptoms and objective inflammation markers (1). Here is what the science shows, where the evidence still has gaps, and what you can practically do with this information.

What Are Emulsifiers and Why Do They Matter in Crohn's?

Emulsifiers are food additives designed to blend ingredients that would normally separate - think oil and water in a mayonnaise, or fat and liquid in a chocolate bar. They give processed foods their creamy texture, extend shelf life, and keep products looking consistent from the factory to your kitchen. That sounds harmless enough, but the sheer scale of their presence in the modern food supply is striking: over 6,000 supermarket products in the UK contain emulsifiers, with at least 63 different types used across the food chain (2).

Common Emulsifiers in Everyday Foods

You will find emulsifiers hiding in places you might not expect. They show up in ice cream, bread, ready meals, sauces, processed meats, plant-based milks, and even some medications. On ingredient lists, they are often identified by E-numbers or chemical names that can be easy to overlook:

• Carrageenan (E407) - extracted from seaweed, commonly used in dairy and dairy alternatives
• Carboxymethylcellulose/CMC (E466) - a synthetic cellulose derivative found in sauces, baked goods, and ice cream
• Polysorbate-80 (E433) - used in ice cream, condiments, and some medications
• Mono- and diglycerides (E471) - one of the most common emulsifiers, found in breads, margarines, and baked goods
• Lecithin (E322) - derived from soy or sunflower, widely used in chocolate and baked goods

Not all of these have been equally studied in the context of inflammatory bowel disease. The three that have drawn the most research attention in Crohn's are carrageenan, CMC, and polysorbate-80 (4).

How Emulsifiers May Affect the Gut

Preclinical research - mostly animal studies and lab experiments - has linked certain emulsifiers to disruption of the intestinal mucus barrier, shifts in the gut microbiota toward more pro-inflammatory species, and increased bacterial translocation (meaning bacteria crossing from the gut lumen into tissue where they trigger immune responses) (4). We will look at these mechanisms in more detail below, but the basic concern is straightforward: additives that alter the gut's protective layers and microbial balance could be especially problematic for people whose guts are already vulnerable to inflammation.

The ADDapt Trial: Largest Dietary RCT in Crohn's Disease

Until recently, evidence linking emulsifiers to Crohn's disease in humans came mostly from preclinical models and observational data. The ADDapt trial changed that. Led by researchers at King's College London, it is the largest and most rigorous dietary intervention trial ever conducted specifically in Crohn's disease (1).

Study Design and Participants

The trial was a multicentre, randomised, double-blind, placebo-controlled study conducted across 19 UK hospitals. It enrolled 154 patients with mild-to-moderately active Crohn's disease, defined as a Crohn's Disease Activity Index (CDAI) score between 150 and 250, plus objective evidence of inflammation (1). Patients were randomly assigned to either a low emulsifier diet (LED) or a control diet in which three specific emulsifiers - carrageenan, CMC, and polysorbate-80 - were supplemented back in capsule form. This clever design meant both groups ate the same whole-food-based diet, with the only difference being whether they were unknowingly consuming those three emulsifiers.

The results of dietary adherence were remarkable: emulsifier intake in the intervention group dropped from a median of 30 grams per day to just 2.5 grams per day (1). That is a dramatic reduction, and it underscores how much of these additives many of us consume without realizing it.

Primary and Secondary Outcomes

The headline findings were striking. At 8 weeks, 49.4% of patients on the low emulsifier diet achieved a clinical response (defined as a 70-point or greater reduction in CDAI) compared with 30.7% of controls. After adjusting for confounders, the relative risk was 3.1 - meaning LED patients were roughly three times more likely to improve (95% CI 1.5-6.6, p=0.003) (1).

Clinical remission also favoured the low emulsifier group, with an adjusted relative risk of 2.1 (p=0.042) (1). And critically, the benefits were not limited to how patients felt. A 50% or greater reduction in fecal calprotectin - an objective stool marker of intestinal inflammation - was nearly three times more likely in the LED group (adjusted RR 2.9, p=0.039) (1).

Of the 154 participants enrolled, 113 (73%) completed the full 8 weeks. No serious adverse events were reported. Perhaps most reassuringly, dietary analysis confirmed that the low emulsifier diet did not impair nutrient intake, and food-related quality of life actually improved in the LED group (6). That last point matters: a dietary intervention is only useful if people can actually stick with it without feeling deprived.

What the Conflicting Evidence Tells Us

Science rarely moves in a straight line, and the emulsifier story is no exception. It is important to look honestly at evidence that does not perfectly align with the ADDapt findings.

The Monash University Exploratory Trial

A smaller 2025 Australian trial led by Fitzpatrick and colleagues at Monash University randomised 24 Crohn's patients to either a high or low emulsifier diet for 4 weeks (3). The results were surprising: 75% of the high-emulsifier group achieved remission compared with 58% in the low-emulsifier group. On the surface, this seems to directly contradict the ADDapt findings.

Why Results May Differ

Before drawing conclusions, the differences in study design are worth noting. The Australian trial was much smaller (24 vs. 154 patients), considerably shorter (4 vs. 8 weeks), and - crucially - both arms ate a healthy, whole-food diet. This means even the "high emulsifier" group was eating well overall. The suggestion here is that the effect of emulsifiers may depend heavily on the overall quality of the diet in which they appear and on the duration of restriction (3).

Conflicting results are entirely normal in nutrition science, where individual variation, study design, and dietary context all shape outcomes. As we explored in our article on the Crohn's Disease Exclusion Diet (CDED), dietary interventions for Crohn's can show meaningful results in well-designed trials while still needing broader replication. The ADDapt trial's larger size, longer duration, double-blind design, and use of objective inflammation markers (calprotectin) make it the strongest evidence to date, but it is not the final word.

How Emulsifiers May Trigger Gut Inflammation

Understanding why emulsifiers might cause trouble helps frame the dietary evidence. Most of what we know comes from preclinical research, but the ADDapt trial's calprotectin results suggest these mechanisms are relevant in humans too.

Disruption of the Mucus Barrier

Your intestinal tract is lined with a mucus layer that acts as a physical barrier, keeping the trillions of gut bacteria at a safe distance from the intestinal wall. Animal studies have shown that CMC and polysorbate-80 can thin this protective mucus layer, allowing bacteria to make direct contact with the epithelial cells underneath (4). When that happens, the immune system responds - and in people with Crohn's, that immune response is already disproportionate and difficult to shut off.

A 2021 mechanistic review published in the Journal of Crohn's and Colitis summarised evidence that emulsifiers increase intestinal permeability - sometimes called "leaky gut" - and alter immune signalling pathways (4). While most of this data remains preclinical, the pattern is consistent: emulsifiers appear to compromise the gut's first line of defense.

Microbiome Changes and Bacterial Translocation

Emulsifier exposure has also been associated with reduced gut microbiome diversity and a shift toward more pro-inflammatory bacterial species in preclinical models (4). As we discussed in our article on gut microbiome diversity in Crohn's disease, the composition of the gut microbiome plays a central role in driving or dampening intestinal inflammation. A less diverse, more inflammatory microbial community is exactly what many Crohn's patients already struggle with, and emulsifiers may be making that imbalance worse.

The ADDapt trial added an important human data point here: the objective reduction in fecal calprotectin in the low emulsifier group supports the hypothesis that removing these additives can meaningfully reduce intestinal inflammation, not just improve symptoms on a questionnaire (1).

Practical Guide: Reducing Emulsifiers in Your Diet

If the evidence has caught your attention, the practical question becomes: how do you actually reduce emulsifier intake in a world where these additives are everywhere?

Reading Labels and Identifying Emulsifiers

The first step is learning to spot emulsifiers on ingredient lists. In the UK and EU, they are identified by E-numbers. The key ones to watch for include:

• E407 - Carrageenan
• E433 - Polysorbate-80
• E466 - Carboxymethylcellulose (CMC)
• E471 - Mono- and diglycerides of fatty acids
• E322 - Lecithin

In the US, Australia, and other countries that do not use E-number labelling, the full chemical name will appear on the ingredient list instead. Categories with the highest emulsifier prevalence include pastries and cakes (95% of products), milk-based drinks (82%), and industrial desserts (81%) (2).

Simple Swaps and Whole-Food Alternatives

Reducing emulsifiers does not require an extreme overhaul. Practical swaps include:

• Yoghurt: Choose natural or Greek yoghurt over flavoured varieties with stabilisers
• Bread: Look for sourdough or bakery bread with simple ingredient lists (flour, water, salt, yeast) instead of commercial sliced bread
• Dressings and sauces: Make your own with olive oil, vinegar, and herbs, or choose brands with short, recognisable ingredient lists
• Ice cream: Opt for brands listing only cream, milk, sugar, and eggs, or make your own
• Spreads: Butter or nut butters instead of margarine or processed spreads
• Milk alternatives: Some plant-based milks use carrageenan or gellan gum; look for ones that do not

The ADDapt dietary analysis confirmed that nutritional adequacy was maintained on the low emulsifier diet, and food-related quality of life actually improved (6). This is encouraging, but if you are already on a restrictive diet for Crohn's, adding another layer of restriction does warrant care. As we covered in our guide to micronutrient deficiencies in Crohn's disease, nutritional gaps are a real concern in this community, and working with a registered dietitian can help ensure you are not trading one problem for another.

Should You Try a Low Emulsifier Diet for Crohn's?

This is the question that matters most, and the honest answer is: it depends on your situation, and it is worth a conversation with your gastroenterologist.

When to Discuss It With Your Gastroenterologist

The ADDapt trial studied patients with mild-to-moderately active Crohn's disease. The results may not apply to those with severe disease, stricturing or fistulising phenotypes, or patients in the immediate post-surgical period (1). A low emulsifier diet is not a replacement for prescribed medications - biologics, immunomodulators, corticosteroids - but rather a potential complementary strategy that may help reduce inflammation alongside medical therapy.

Working with a registered dietitian is recommended, especially for patients already managing other dietary restrictions. If the approach interests you, consider bringing the ADDapt trial data to your next gastroenterology appointment. Having specific evidence to discuss gives both you and your doctor a concrete starting point rather than a vague conversation about "eating cleaner."

Limitations of the Current Evidence

Transparency matters, so here is what we do not yet know:

• The full peer-reviewed ADDapt paper has not yet been published; results were presented as an abstract at ECCO 2025 (1). The full paper will provide more detail on subgroup analyses, long-term follow-up, and secondary endpoints.
• The trial was conducted in the UK, and replication in other populations with different dietary patterns is still needed (5).
• We do not yet know whether the benefits persist beyond 8 weeks, or whether emulsifier restriction works differently depending on disease location, medication use, or microbiome profile.
• The smaller Australian trial raises legitimate questions about whether emulsifier effects depend on overall diet quality (3).

None of these limitations invalidate the ADDapt findings, but they are reasons to approach the results with informed optimism rather than certainty. The evidence is promising, the approach appears safe and sustainable, and for many of us the practical changes are relatively straightforward. That is a combination worth paying attention to.

References

1. Whelan, K., et al. Emulsifier restriction is an effective therapy for active Crohn's disease: the ADDapt trial. Journal of Crohn's and Colitis, 2025. Read study
2. King's College London. New research presented at ECCO Congress on low emulsifier diet and Crohn's disease. 2025. Read article
3. Fitzpatrick, J.A., et al. Clinical Trial: The Effects of Emulsifiers in the Food Supply on Disease Activity in Crohn's Disease. 2025. View on PubMed
4. Naimi, S., et al. Food Additive Emulsifiers and Their Impact on Gut Microbiome, Permeability, and Inflammation: Mechanistic Insights in IBD. Journal of Crohn's and Colitis, 2021. Read study
5. The ADDapt Diet in Reducing Crohn's Disease Inflammation. ClinicalTrials.gov, 2025. View trial registration
6. Whelan, K., et al. Emulsifier restriction does not impair nutrient intake and improves food-related quality of life in active Crohn's disease: dietary analysis of the ADDapt trial. Journal of Crohn's and Colitis, 2025. Read study