Why Does Coffee Make Us Poop? Scientists Gave Coffee to Rats to Find Out

Increases sympathetic activity which activates the lumbar plexus of the rectum and anus. As with most cause-effect stimuli, a pavlovian response may occur. Indeed, once the association is made, bowel activity may be triggered simply by the scent of coffee. http://bit.ly/1VMjaZw
from Rajesh Harrykissoon, MD