Bottoms up! Dave Stock

Down the microscope, they looked like tiny, sperm-like things, hatching out of their hidey-holes. A few minutes later, I was swallowing dozens of larval-stage parasites, washed down in one gulp of milk. An hour later, these egg-like organisms were probably hatching out as worms in my gut.

“You swallow the egg-like sac and in the small intestine bile triggers the larvae to come out,” explains Judy Chinitz, co-founder of Biome Restoration, a company in Lancaster, UK, that sells vials of larval-stage rat tapeworms, Hymenolepis diminuta. “They eat microscopic bits of food, but die in 10 days.”

The company is shipping these to around 2000 customers worldwide. The UK Medicines and Healthcare products Regulatory Agency (MHRA) has cleared them for sale, provided the company makes no specific health claims. “We can say they ‘maintain good health’, and that’s it,” says Marc Dellerba, another co-founder.


Biome Restoration was set up in response to growing online demand for live parasite products, and to provide a cheaper alternative to the pig whipworms other firms sell. The company doesn’t know what reasons its customers have for taking the worms, because of MHRA regulations. “We can’t ask, and we don’t, and we can’t collect clinical data, although it would be wonderful if we could,” says Dellerba.

Helminth high?

To mimic the tapeworm’s natural life cycle, Dellerba shows me how the team feeds infected rat faeces to mealworm beetles. When the beetles consume the eggs, these develop into the juvenile, egg-like stage that is extracted from dead beetles and sold to customers following sterilisation.

After swallowing some of these, I was warned that I might experience a feeling of bliss called a “helminth high” the day after. I did feel slightly more upbeat when I woke up the next day, but this may just have been a placebo effect prompted by what I had been told.

Other than that, the only difference I noticed over the following 10 days was my stools turning green for three or four days – although this could have been caused by something else. My family and colleagues were a little disgusted by what I had done, but were fine as long as there was no risk I could pass the parasite on to them.

The team at Biome Restoration say they are pleased to see that a rival product, involving pig whipworms, is being considered for approval as a food ingredient in Germany. “I hope it achieves official food status,” says Chinitz. “It will mean there’s finally recognition from regulators that biome enrichment with benign helminths is akin to simply taking another form of probiotic.”



Read more: Parasitic worm eggs may soon be legally sold as food in Germany