Bifidobacteria are a genus of probiotic bacteria commonly found in the human gut, and they have been investigated for their potential to modulate immune function and reduce inflammation. There is emerging scientific evidence suggesting that Bifidobacteria supplementation may be beneficial in some autoimmune disorders, particularly those involving the gut, such as inflammatory bowel disease (IBD) and ulcerative colitis. Preclinical studies in animal models have shown that specific strains of Bifidobacteria can enhance regulatory T cell responses, reduce pro-inflammatory cytokine production, and help maintain gut barrier integrity. Small-scale human trials and observational studies have reported improvements in symptoms and inflammatory markers in patients with IBD and related conditions following probiotic treatment that includes Bifidobacteria.

However, the overall quality of evidence is limited. Most clinical trials to date are small, heterogeneous in design, and often combine Bifidobacteria with other probiotic strains, making it difficult to attribute effects specifically to Bifidobacteria. There is even less direct evidence for the use of Bifidobacteria in systemic autoimmune diseases such as rheumatoid arthritis, lupus, or multiple sclerosis. Thus, while there is a scientific rationale and some early evidence for the use of Bifidobacteria in certain autoimmune and inflammatory disorders—especially those involving the gut—the clinical evidence remains preliminary. Larger, high-quality randomized controlled trials are needed to establish efficacy and clarify mechanisms.