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Probiotics (Bifidobacterium) — Frequently Asked Questions

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

Frequently Asked Questions

Why do Bifidobacterium levels decline with age?

Bifidobacterium abundance drops from ~90% of the infant gut to <5% in elderly adults. This decline is driven by diet changes (less breast milk/fiber), antibiotic exposure, and age-related immune changes. Lower Bifidobacterium levels correlate with increased gut inflammation, and supplementation may partially restore this population.

What is the best Bifidobacterium strain for IBS?

B. infantis 35624 (sold as Align) has the strongest evidence from a large RCT (n=362) showing significant improvement across all IBS subtypes at just 1 billion CFU/day. It is one of the few probiotics with a specific AGA conditional recommendation for IBS.

Can Bifidobacterium help with anxiety?

Emerging evidence suggests yes. B. longum 1714 reduced cortisol and perceived stress in a controlled trial (Allen et al., 2016). This works through the gut-brain axis — Bifidobacterium produces GABA and modulates vagal nerve signaling. However, this research is still emerging and probiotics should not replace anxiety treatment.

Full Probiotics (Bifidobacterium) Guide

References

  1. (). Efficacy of an encapsulated probiotic Bifidobacterium infantis 35624 in women with irritable bowel syndrome. American Journal of Gastroenterology. DOI
  2. (). Evaluation of the immune benefits of two probiotic strains Bifidobacterium animalis ssp. lactis BB-12 and Lactobacillus paracasei ssp. paracasei L. casei 431 in an influenza vaccination model. British Journal of Nutrition. DOI