Intestinal worms may prevent bowel cancer; as such, a health drink containing whipworm eggs to replenish your body's supply of the
parasites symbionts may soon go on the market in Europe. The worms will be the pig variety, which doesn't survive long in humans, and is less likely to cause complications. (via FmH)
I wonder how long until we all have personalised populations of genetically engineered ex-parasites, modified to eliminate potential health problems long before any symptoms would arise, in our bowels, bloodstreams and elsewhere.
The title of the article says cancer. The body of the article mentions IBD, colitis, and Crohn's. IBD, colitis, and Crohn's are an entirely different thing than cancer.