Bifidobacterium (various species) has been investigated for its potential to support or treat eczema, particularly atopic dermatitis, based on the hypothesis that modulation of the gut microbiota may influence immune responses and skin health. Several randomized controlled trials (RCTs) and meta-analyses have explored the effects of Bifidobacterium supplementation, usually as part of probiotic mixtures, in infants and children with eczema or at risk of developing eczema.

Results from these studies are mixed. Some RCTs have reported modest reductions in eczema severity or incidence in children given Bifidobacterium-containing probiotics, especially when administered prenatally to mothers and/or postnatally to infants. However, other trials have found no significant benefit compared to placebo. Meta-analyses and systematic reviews (e.g., Zuccotti et al., 2015; Kim et al., 2014) generally conclude that while there is some evidence of a preventative effect in high-risk infants, the overall clinical relevance is limited and the quality of evidence is moderate to low.

No major guidelines currently recommend Bifidobacterium as a standard treatment for eczema, and benefits, if any, appear to be strain-specific and population-dependent. Thus, scientific evidence exists but is inconsistent and not robust enough to support routine clinical use.