Year: 2024
Type: article
Study designs: Randomized Controlled Trial, Clinical Trial
Abstract: BACKGROUND: The potential impact of specific food additives, common in Western diets, on the risk of developing type 2 diabetes is not well understood. This study focuses on carrageenan, a widely used food additive known to induce insulin resistance and gut inflammation in animal models, and its effects on human health. METHODS: ) participated. The intervention involved oral intake of carrageenan (250 mg) or placebo in the morning and in the evening and each intervention lasted 2 weeks. The primary outcome measured was insulin sensitivity (using oral glucose tolerance test [OGTT] and hyperinsulinaemic-euglycaemic clamp). Additional end-points included whole body and hepatic insulin sensitivity, MRI-measured brain inflammation and insulin resistance, intestinal permeability (via lactulose-mannitol test and plasma zonulin levels), and gut microbiome composition. Immune-cell activation and pro-inflammatory cytokine release from peripheral blood mononuclear cells were measured. RESULTS: Overall insulin sensitivity did not show significant differences between the treatments. However, interactions between BMI and treatment were observed (OGTT-based insulin sensitivity index: p=0.04, fasting insulin resistance: p=0.01, hepatic insulin sensitivity index: p=0.04). In overweight participants, carrageenan exposure resulted in lower whole body and hepatic insulin sensitivity, a trend towards increased brain inflammation, and elevated C-reactive protein (CRP) and IL-6 levels compared to placebo. Additionally, carrageenan was associated with increased intestinal permeability. In vitro natural killer (NK-)cell activation and increased pro-inflammatory cytokine release were found after carrageenan exposure in the participant's peripheral blood mononuclear cells. CONCLUSIONS: These findings suggest that carrageenan, a common food additive, may contribute to insulin resistance and subclinical inflammation in overweight individuals through pro-inflammatory mechanisms in the gut. Further investigation into the long-term health impacts of carrageenan and other food additives is warranted. TRIAL REGISTRATION: NCT02629705.
Source: BMC Medicine
Authors: Robert Wagner, Janine Buettner, Martin Heni, Louise Fritsche, Stephanie Kullmann, Moritz Wagmüller, Andreas Peter, Hubert Preissl, Jürgen Machann, Reiner Jumpertz von Schwartzenberg, Andreas L. Birkenfeld, Ulrich-Frank Pape, Gerrit van Hall, Peter Plomgaard, Hans-Ulrich Häring, Andreas Fritsche, Kelsey N. Thompson, Reinhild Klein, Norbert Stefan
Institutions: Harvard University, Helmholtz Munich, Düsseldorf University Hospital, Universitätsklinikum Tübingen, Deutsches Diabetes-Zentrum e.V., German Center for Diabetes Research, Heinrich Heine University Düsseldorf, University of Tübingen, Charité - Universitätsmedizin Berlin, Universität Ulm, University Hospital Ulm, Asklepios Klinik St. Georg, Asklepios Kliniken Hamburg, University of Copenhagen, Rigshospitalet
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,890
OpenAlex ID: W4404717989