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5 Reasons Parasites Are Beneficial to Earth

        Science | Green Science

Parasites Might Cure Autoimmune Diseases

Most sane people would never intentionally infect themselves with a parasite -- especially some nasty stomach worm. But what if we told you that some types of parasites could actually help you? In recent years, scientists have discovered that certain parasites have the ability to interfere with autoimmune diseases. Of course, that doesn't mean that just anyone should go out and intentionally infect themselves with stomach worms. But in some select cases where the benefits outweigh the costs, getting a parasite is a legitimate source of medicine.

One of the pioneers of this type of radical parasite therapy research is Tufts University gastroenterologist Joel Weinstock, who had a revelation of sorts when exploring the question of why diseases, from asthma to multiple sclerosis, are on the rise in developed countries but not in undeveloped parts of the world. Weinstock discovered a possible answer: worms [source: Baker].

Weinstock's theory -- which is still being tested and hasn't yet been proven -- is that there's a direct correlation between a lack of intestinal worms and a rise in autoimmune diseases. In developed countries like the United States we've done an excellent job -- some would say too good a job -- avoiding parasitic worms, but we may be paying the price in the form of other, even more harmful diseases.

Weinstock began thinking about helminthic therapy in the early 1990s, when he noticed how prevalent inflammatory bowel disease had become in North America. At the same time, he realized that parasitic worms, or helminths, have a unique effect on their human hosts. Instead of inducing inflammation (the body's normal response to invasion), they actually calm the immune system. According to the theory, because people have lived with helminths through much of history, the human immune system has evolved to fight them, and when worms are removed entirely, the body's immune system turns against itself. Helminthic therapy, or worm therapy, may emerge as a legitimate field of medicine, but it's still very new and few studies have been done to date [source: Velasquez-Manoff].