Aromatherapy makes sense: you sit in a darkened room, smell some nice things, and maybe listen to some womb music. Homeopathy I understand: you feel a bit down, so you buy expensive water from someone nice and wait for the placebo effect to kick in.
But colonic irrigation - squirting large quantities of water into a place where nothing should be squirted - seems less appealing. As with enemas, which are less invasive and are used in conventional medicine, it can relieve constipation. However, its main purpose relates to the theory of autointoxication. Autointoxication is the idea that waste matter becomes encrusted on the walls of our intestine and releases toxins back into our bloodstream, leading to illness. This waste can be removed by sticking a tube up your anus and pumping in water.
Advocates trace colonic irrigation's origins to the ancient Egyptians, who believed that disease originated in the intestines. Health-conscious pharaohs redirected Nile water from farming towards this less conventional form of irrigation.
The Egyptians may well be the undisputed leaders in building large, square-based pointy objects, but medicine has moved on. Katie Bolland is a spokesperson for the UK Association and Register of Colonic Hydrotherapists, a private body which accredits and maintains standards at more than 100 affiliated clinics and at seven approved colleges. I ask her about the scientific evidence for autointoxication. "There is a recent survey showing high levels of patient satisfaction following colonic hydrotherapy," she says. Great. Does she know of any peer-reviewed papers confirming the theory of autointoxication? Err, no.
The problem with autointoxication is that very few scientists believe it exists. Not one study has backed it up in practice. For perhaps this reason, no one has bothered to conduct a proper clinical trial. The basis for colonic irrigation is implausible and, what's more, the treatment has risks. These include perforation of the colon, loss of important colon bacteria and electrolyte imbalances. There have even been reported deaths.
Extraordinary practices, particularly those with risks attached, need extraordinary evidence. Put it another way; if I'm shoving something up my bum, then I need to be damn sure that it's safe and that there's a good reason. This procedure fails on both counts.
Why then, does a survey apparently imply high levels of patient satisfaction? Maybe after doing something as ridiculous as voluntarily putting a hose pipe up their arse, people are ashamed to admit it may have been pointless. Or maybe there is something even more sinister at work. "Why are we in Britain obsessed with colonic irrigation?" asks Edzard Ernst, professor of complementary medicine at Exeter University. "It's unpleasant and disgusting." He pauses. "Maybe that's what the British like."
