Bifidobacterium lactis
Bifidobacterium lactis is a bacterial species found in the gut and in fermented milk products. It is one of the most common bacteria in probiotic products.
What did the earlier constipation trial find?
A French trial tested HN019 in 228 adults for 28 days at 1 or 10 billion colony-forming units daily. The main analysis found no benefit for transit time or symptoms. 1
A favorable bowel-frequency finding came from a subgroup defined after the main analysis, so it needs confirmation. 1
Did a larger follow-up confirm benefit?
In 2024, a trial of 229 adults found no advantage over placebo for complete spontaneous bowel movements after eight weeks. The tested product supplied approximately 4.69–7 billion viable cells daily during the study. 2
What does the newest French study add?
An eight-week trial published in 2025 also found HN019 no better than placebo for constipation. It was funded by a company affiliated with the strain manufacturer. 3
What is outside this review?
This page does not evaluate every B. lactis strain or claims about immunity, histamine or skin symptoms.
Effects by health goal
Open an effect to see the studies behind its rating. Bars show the size of the effect; the letter grades the evidence.
Gut Health4 effects
No study is linked to this rating.
No study is linked to this rating.
Immune Support4 effects
No study is linked to this rating.
No study is linked to this rating.
Hair & Skin1 effect
No study is linked to this rating.
Other effects2 effects
All studies
13 publications are linked to Bifidobacterium lactis, newest first.
Sources
- Effect of an 8-Week Bifidobacterium lactis HN019 Supplementation on Functional Constipation: A Multi-Center, Triple-Blind, Randomized, Placebo-Controlled Trial Molecular Nutrition & Food Research, 2025