Concerns have been raised about the growing trend for DIY faecal transplants, with experts fearing such attempts could put individuals at an increased risk of HIV and hepatitis as well as conditions ranging from Parkinson’s and multiple sclerosis to obesity and sleep disorders.

The transfer of faeces from one human to another has gained attention as a growing number of studies have suggested links between microbes in the gut and a host of health problems, from autoimmune diseases to anxiety.

Currently, implanting a “healthy” gut microbiome into a recipient is one of the treatments used in medical settings to tackle the superbug Clostridium difficile. But with some claiming the procedure could help a wide range of conditions, a plethora of YouTube videos have sprung up revealing in how to carry out faecal transplants at home.

Experts have raised concerns, stressing that screening is vital to prevent problematic microbes, including those linked to MS and Parkinson’s, from being transferred to recipients – a particular concern for those attempting a DIY procedure.

“Given that we know that these are things that in mice, at least, can be transmitted by the microbiome, it is not cause for panic yet, but it is certainly cause for concern that the same might be true in humans,” said Rob Knight, professor of paediatrics, computer science and engineering at the University of California San Diego, who is presenting his latest work on the microbiome at the meeting of the American Association for the Advancement of Science in Austin this week.

While research has long suggested that obesity could be linked to the microbiome, recent studies have suggested a host of other issues, including sleep disorders, could also be associated with changes in the gut flora. Furthermore, Knight noted that studies have revealed that there are differences in the microbiomes of those with and without conditions such as multiple sclerosis and Parkinson’s disease. “[Very recently] we were able to show that you can transmit aspects of the disease from humans into mice by transmitting the microbiome,” said Knight, although he noted that a particular genetic change was needed in the mice in the case of Parkinson’s.

Currently faecal transplant is used as a treatment for Clostridium difficile infections – the goal being to reseed the gut with “good” microbes. Donors are screened for conditions including infectious diseases and parasites, while those with autoimmune diseases, a history of cancer or gastrointestinal problems are excluded as donors. However Knight stressed that with research throwing up an ever-increasing number of conditions linked to the microbiome, screening is set to become increasingly important. “Tests that look at the whole microbiome profile are still at the research stage,” he said.

The risk of inadvertently transferring either diseases or problematic microbes, he added, are even greater for individuals taking matters into their own hands – a trend Knight said is growing. “It is regrettably something that is increasing in frequency,” he said, noting that in particular those with incurable diseases are often willing to try anything, even if evidence for a procedure is scanty.

The fear that faecal transplants could give recipients more than they bargained for is underscored by a case study from 2015 in which a woman undergoing a faecal transplant for a C. difficile infection ended up becoming obese after receiving a stool sample from her healthy but overweight daughter.



Knight added that his team is currently part of a project that will “Basically capture stool from donors and recipients of faecal transplants on a national scale in the United states so we can get a sense of long term outcomes not just short term outcomes.”



The team is also joining forces with IBM’s Watson to develop a system that can help researchers, patients, reporters and doctors sift and understand the growing body of research on the microbiome. “Human intelligence just can’t keep up with all the literature that is coming out on the microbiome, and so if we can use artificial intelligence to advance our capabilities that will make it really helpful,” Knight said.

