Researchers led by Hiroshi Ohno at the RIKEN Center for Integrative Medical Sciences (IMS) in Japan have discovered why smoking tobacco helps people suffering from ulcerative colitis, a chronic disease typified by inflammation of the large intestine. Published in the scientific journal Gut, the study shows that smoking produces metabolites that encourage bacteria from the mouth to grow in the large intestines where they trigger an immune response. These findings imply that protection against...