Probiotics and Constipation

You may have heard that probiotics help treat constipation. But how, you might ask? Thanks to a lecture on probiotics and children's health that I attended today, I know understand the mechanism:

Healthy, Happy Gut. 

Probiotics introduce good bacteria into the gut. ---> While in the gut, these good bacteria produce short chain fatty acids (such as butyric acid, propionic acid, and lactic acid). ---> The presence of these short chain fatty acids lowers the pH of the gut. ---> A lower gut pH stimulates peristalsis (increased wave-like contractions). ---> These contractions help move stool out of the gut. ---> Decreased incidence of constipation. ---> Healthier gut overall.