I'm continually impressed with some of the articles I've read in Scientific American. If you're focused on causal factors behind health issues, finding solid information correlating an addressable causal factor with a common health issue is highly empowering to say the least. Here is a quote from a recent article discussing environmental air pollutants (such as soot, carbon monoxide, sulfur dioxide, VOC's) as a possible causal factor for bowel diseases such as Crohn's:
"Some evidence suggests inhaling fine particles, or soot, may disrupt the immune system and trigger inflammation in the gut by making it more permeable and altering its normal bacteria."
-Scientific American, September 20, 2013
How do we apply this information? We would all do well to make every effort to reduce our exposure to outdoor and indoor air pollutants. There is also much we can do to help the body excrete toxins that it have already accumulated.