In the 1840s a Japanese clergyman, Dr Mikao Usui, rediscovered ancient manuscripts describing a form of healing called reiki. Reiki is a Japanese word meaning 'universal life energy'. The idea behind reiki was that there are paths of energy that flow through our bodies and when one or more of these paths becomes blocked or disturbed this leads to illness. Reiki therapy is a way of correcting this by placing hands over certain parts of the body to rechannel the energy flows and reverse the problem.
Reiki involves sessions of about an hour where the therapist put their hands on different parts of the body, for several minutes at a time. The hands are placed quite lightly and stay quite still, there is no actual massage or manipulation involved. There is also no need to get undressed, the hands are placed over the clothed areas of the body. The treatment usually involves two or three sessions over a week or so followed by as break and then the treatment can be repeated.
A variation is called second degree reiki, where therapists claim to be able to send their healing forces over a distance, without any need for contact with their 'patient'.
There is absolutely no evidence that reiki can help to treat or cure cancer. Some people do say, however, that having reiki has helped them cope with the sickness that can occur during chemotherapy and there are some reports of people with pain associated with cancer having some relief as a result of reiki.
Reiki therapy is not available on the NHS.
So although it would be dangerous, to use Reiki as an alternative to normal treatments for cancer, for some people it may sometimes help in coping with some of the problems caused by the illness.

