Carrageenan and inflammation in Crohn's disease gut cells
What it found
In lab tests on gut cells from people with Crohn's disease, carrageenan increased inflammatory markers but did not change how leaky the cells were.
The effect was stronger when inflammation was already present.
What they found
Animal and lab studies
Leakiness unchanged
Carrageenan did not change the leakiness of the gut cell layers, whether or not inflammation was present. This was measured by electrical resistance across the cell layer.
Inflammatory genes up
In cells from Crohn's disease patients, carrageenan increased the activity of genes for three inflammatory signals: TNF, IL8, and IL1B. This happened in both inflamed and non-inflamed cells.
Cytokine release changed
Carrageenan changed the release of several cytokines from the patient cells. In inflamed cells, levels of IL-6, IL-13, IL-2, IL-4, and IL-10 went up, while IL-8 went down.
Barrier gene changes
Carrageenan caused small changes in genes related to the gut barrier. Some tight junction genes increased, and a mucus gene called MUC5AC decreased in inflamed cells.
What the authors conclude
“This study revealed that the dietary emulsifier carrageenan has direct pro-inflammatory effects on intestinal epithelial cells from patients with Crohn’s disease, without affecting permeability.”
Also in their conclusions
- They conclude that dietary carrageenan increased inflammatory markers and changed cytokine release in gut cells from Crohn's disease patients, without affecting permeability.
- They suggest that carrageenan restriction can be beneficial in patients with active disease.
- They support a diet low in processed foods and emulsifiers for patients with inflammatory bowel diseases, especially during active inflammation.
How it was done
The authors wanted to find out whether the food additive carrageenan can change the leakiness and inflammation of the gut lining. They focused on Crohn's disease because diet is thought to play a role in it.
They grew gut cells in the lab: a mix of Caco-2 and HT29-MTX cells, and cells grown from gut biopsies of 5 people with Crohn's disease. These cells were exposed to carrageenan for 24 or 48 hours, with or without an added mix of inflammatory triggers.
What it can’t tell you
- These are lab tests on cells, not studies in people. They cannot show what happens when someone eats carrageenan.
- The cells were exposed for only 24 to 48 hours, so the study cannot show the effects of long-term daily consumption.
- The study looked at carrageenan alone, not in combination with other food additives or the gut microbiome.
Who paid
- Funding
- Funded by Research Foundation Flanders (FWO); Research Foundation Flanders (FWO), Belgium; Flemish Crohn's and Colitis; Flemish Crohn's and Ulcerative Colitis; Clinical Research Fund (KOOR) (from the PubMed record).
- Conflicts
- B.V. receives research support from AbbVie, Biora Therapeutics, Landos, Pfizer, Sossei Heptares and Takeda; receives speaker’s fees from Abbvie, Biogen, Bristol Myers Squibb, Celltrion, Chiesi, Falk, Ferring, Galapagos, Janssen, Lily, MSD, Pfizer, R-Biopharm, Sandoz, Takeda, Tillots Pharma, Truvion and Viatris; receives consultancy fees from Abbvie, Alfasigma, Alimentiv, Applied Strategic, Astrazeneca, Atheneum, BenevolentAI, Biora Therapeutics, Boxer Capital, Bristol Myers Squibb, Galapagos, Guidepont, Landos, Lily, Merck, Mylan, Nxera, Inotrem, Ipsos, Janssen, Pfizer, Progenity, Sandoz, Sanofi, Santa Ana Bio, Sapphire Therapeutics, Sosei Heptares, Takeda, Tillots Pharma, and Viatris; stock options Vagustim. M.F. receives financial support for research from AbbVie, Biogen, EG, Janssen, Pfizer, Takeda, and Viatris; receives speakers’ fees from AbbVie, Biogen, Boehringer Ingelheim, Falk, Ferring, Janssen-Cilag, MSD, Pfizer, Takeda, Truvion Healthcare, and Viatris; and receives consultancy fees from AbbVie, Agomab Therapeutics, Boehringer Ingelheim, Celgene, Celltrion, Eli Lilly, Janssen-Cilag, MRM Health, MSD, Pfizer, Takeda, and Thermo Fisher. S.V. receives financial support for research from AbbVie, J&J, Pfizer, Takeda, and Galapagos; receives speakers’ and consultancy fees from AbbVie, Abivax, AbolerIS Pharma, AgomAb, Alimentiv, Arena Pharmaceuticals, AstraZeneca, BMS, Boehringer Ingelheim, Celgene, Cytoki Pharma, Dr Falk Pharma, Ferring, Galapagos, Genentech-Roche, Gilead, GSK, Hospira, Imidomics, Janssen, J&J, Lilly, Materia Prima, Mestag Therapeutics, MiroBio, Morphic, MrMHealth, Mundipharma, MSD, Pfizer, Prodigest, Progenity, Prometheus, Robarts Clinical Trials, Surrozen, Takeda, Theravance, Tillots Pharma AG, VectivBio, Ventyx, Zealand Pharma. C.M. is chair of the KU Leuven Fund “Nutrition,” a donation-based fund to stimulate research on nutrition. Recipient of travel/accommodation expenses and small participation fee (< 100€/meeting) as a member of working groups of the Belgian Superior Health Council and Belgian Federal Agency of the Safety of the Food Chain. Recipient of travel/accommodation expenses as member of the scientific advisory body of the EU Joint Programme Initiative Healthy Diet, Healthy Life, as co-chair ILSI Europe Task Force Dietary Intake and Exposure, as member ILSI Europe Task Force Nutrient Intake Optimisation. Recipient of honoraria (< 500€/year) as an active member of the advisory board of NutriNews (Belgian Nutrition Information Center). Recipient of honoraria as jury-member of nutrition-related awards and reviewing EU-grants. Recipient of royalties form a textbook (Handboek Voeding, ACCO). Honoraria are used to support research of PhD Students. J.S. receives financial support for research from Galapagos and Viatris; receives speakers’ fees from Abbvie, Falk, Takeda, Pfizer, Galapagos, Ferring, Janssen, and Fresenius; and does consultancy for Janssen, Ferring, Fresenius, Abbvie, Galapagos, Celltrion, Pharmacosmos, and Pharmanovia. All other authors have nothing to disclose.
- Authors work at
- Translational Research Center for Gastrointestinal Disorders (TARGID), Belgium
The paper
- Title
- Dietary Carrageenan Amplifies the Inflammatory Profile, but not Permeability, of Intestinal Epithelial Cells from Patients With Crohn's Disease
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Vissers E, Wellens J, Giorio L, et al (2025). Dietary Carrageenan Amplifies the Inflammatory Profile, but not Permeability, of Intestinal Epithelial Cells from Patients With Crohn's Disease. Inflammatory bowel diseases. doi:10.1093/ibd/izae306Free full textPubMed 39720875DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error