Helminths are worms, like roundworms or hookworms, that can live in human intestines. They are not as prevalent in developed nations, like the United States, but are very common in more traditional societies; nearly 20% of people world wide have helminths, and upwards of 70% of people in some communities have them. There has been recent speculation that the presence and absence of helminths can lead to the so-called "diseases of wealth", due to their positive effects on the microbiome and reducing the inflammatory effects of the immune system. This has even led to a cottage industry providing helminthic therapy, where helminths are purposely ingested.
An article was recently published in PLoS ONE about the effect of gut helminths on the microbiome. In the study, a cohort of 51 individuals from Malaysia had their stool samples tested for microbial diversity and for the presence of helminths. The study showed that people with helminths had a richer diversity and greater number of bacteria in their gut. They also discovered a greater amount of specific bacterial taxa from those that had helminths and those that didn't. In addition, the authors mention other studies done in developed nations that have shown the same effect. The paper concludes that helminths may be increasing gut microbial diversity, and increased diversity has been repeatedly linked to improved health, but as always this association does not necessitate causation.
While an interesting paper, we don't suggest any of our readers to go out and eat ringworm any time soon. Helminths can of course, have other negative consequences!