If you see Angie Buxton-King at work on the cancer wards at University College Hospital in Central London, she looks like any other medic: alert, down to earth, overworked. But her talents are different - she is a spiritual healer, one of a handful on the NHS payroll. But she hopes that, with new research and regulation of healing, there may soon be more like her.

Cancer patients at UCH are offered a range of complementary treatments as well as chemotherapy and radiotherapy. These are provided by a four-strong team led by Buxton-King: two healers (Angie and her husband Graham), a counsellor and a massage therapist.

Their services are in great demand, which is hardly surprising: statistics suggest that about 90 per cent of cancer patients avail themselves of some form of complementary medicine.

In a small room behind the team's office, a CD of relaxing music is playing. The patient lies on a couch while Buxton-King runs her hands over him or her to “channel the healing energy”. Many patients report feeling heat emanating from the hands, and a feeling of profound relaxation and peace. Each session lasts for 15 minutes.

So how did this all start? In the late 1990s Buxton-King's son, Sam, was fighting leukaemia. “He wasn't expected to live longer than three months,” she says, “so we looked at alternative ways of helping him, and during the three more years that he lived, it became obvious that his quality of life was improved by healing.”

Buxton-King wanted to help other NHS cancer patients, and first offered her services to Great Ormond Street hospital. They were sceptical, so she went to UCH, where she asked Dr Stephen Rowley, the clinical director of haematology, for a chance to prove the need for her services and was taken on for a trial month, one day a week.

“At the end of that time they were very interested,” says Buxton-King. “The whole ward benefited - staff as well as patients.”

She was taken on for two days a week, and eventually made manager of the complementary team. Four other healers also work at UCH, paid for by a charity that Angie and Graham set up.

Now the team is fully accepted as integral to the treatment on the cancer wards. Dr Maria Michelagnoli, a paediatric and adolescent consultant oncologist, says: “I was a sceptic at first, but you can't question the results. I'd be devastated if we lost these professionals now.”

Dr Rowley says: “I see experienced doctors call for the healer to help to support a child having a cannula put into a vein. Patients benefit in many ways.”

Other experts concur. Derryn Borley, the head of support services at Macmillan Cancer Support, says: “There is evidence that it improves patients' moods and can help with physical symptoms. It also helps people to go through chemotherapy.”

Spiritual healing may be hands-on, hands-off or conducted from a distance. Practitioners say that they are channelling energy from a higher source. It is distinct from faith healing, requiring no shared religion between healer and patient.

Some scientists believe that, if it works, it is the result of a “healing intention” in the healer's mind. This might also help to explain why praying for the sick can help them to recover, as some research has suggested it does. A study in Israel, for instance, published in 2001, looked at two groups of people with blood infections, one prayed for, the other not. It indicated that the prayed-for patients had shorter stays in hospital, stayed feverish for less time, and were more likely to survive.

Professor Edzard Ernst, of Exeter University, studied 110 patients with chronic pain, half of whom were treated by professional spiritual healers, the other half by actors pretending to be healers. “The results were staggering,” he wrote. “Several patients practically abandoned their wheelchairs. But there were no differences between the groups - if anything, the control patients fared slightly better. This suggests that spiritual healing is a strong placebo but not much more.”

Naturally, full-time healers dispute this. “I wanted to see if it was true so for a while I just practised on animals. I still saw positive results,” says Buxton-King.

Patients also believe that something “real” is happening. Dr Anil Wijetunge, an NHS tutor, became sick with bone marrow cancer in 2005 and received spiritual healing at UCH. “Something was going on with the energy,” he says. “The healers knew which part of me was suffering the most.”

To raise funds for more NHS healers, Buxton-King set up the Sam Buxton Sunflower Healing Trust, which held “Sunflower Jam” concerts in 2006 and 2007. The next concert is due to feature a re-formed Deep Purple.

Could the NHS provide more support? Baroness Finlay, a professor of palliative medicine at Cardiff University School of Medicine, says: “It's not enough to say that spiritual healing makes patients feel better. Having a haircut might as well, but that doesn't mean the NHS should pay for it. We need evidence that it works.”

Anecdotal evidence from former patients is in favour, but some healers accept that further proof will be required - which is partly why Buxton-King is carrying out a trial this year on reiki, a form of spiritual healing used in Japan, which will be funded by UCH.

Another hotly debated area is regulation. A government working group chaired by Professor Mike Pittilo recently recommended statutory regulation for Chinese medicine and acupuncture, and last month Professor Pittilo wrote in The Times: “There is honest recognition that the evidence base for many [complementary] therapies is thin but, given the public demand for treatment, this should be addressed alongside the introduction of statutory regulation, rather than as a prerequisite.”

Regulating spiritual healers would be quite a challenge. There are 15,000 at work in the UK, and several governing bodies. But, says Buxton-King, “it's the only way it's going to go forward”.

The 2008 Sunflower Jam is on Thursday, September 25, in London. For details go to www.thesunflowerjam.com