Lactobacillus casei

Lactobacillus casei is better able to pass gastric acid and bile. After live cells reach the colon they stimulate motility, increase stool frequency, and soften stools. Daily fermented-milk trials are the most common, suiting people with long-term straining or long intervals between stools. Weekly stool frequency and straining match this use better than a single-day diarrhea rescue.

This species has a more complete peptide-hydrolyzing enzyme set and can predigest casein and milk protein, reducing use of undigested protein by putrefactive bacteria in the gut. Post-meal gas and a heavy feeling after dairy are the more often matched occasions. After the milk-protein load falls, post-meal waist girth is less likely to balloon at once, and heaviness also clears faster.