The use of Bifidobacterium (mixed strains) to support or treat eczema, particularly atopic dermatitis in infants and children, is primarily justified by scientific investigation, although the evidence is still considered preliminary and not robust. Several randomized controlled trials and meta-analyses have explored the potential of probiotics, including mixed Bifidobacterium strains, to reduce the severity or incidence of eczema. Some studies suggest that supplementation with Bifidobacterium (often combined with Lactobacillus species) during pregnancy and early infancy may decrease the risk of developing eczema in high-risk children. Proposed mechanisms include modulation of immune responses, enhancement of gut barrier function, and promotion of a healthier gut microbiota.

However, results are inconsistent, with some studies showing modest benefits and others showing no significant effect. Meta-analyses tend to find small, statistically significant reductions in eczema risk or severity, but the clinical relevance of these findings is debated. Professional guidelines, such as those from the World Allergy Organization, state that there is low to moderate quality evidence supporting probiotic use (including Bifidobacterium) for eczema prevention in some populations, but they do not universally recommend it due to heterogeneity in results and uncertainty about optimal strains, doses, and timing. Thus, while there is scientific interest and some evidence, it is limited (rated 2/5).