Of course, they would appear to be invisible, if not non-existent, when we use our eyes or any current technological aid. But the proof of their existence can be surmised by the effectiveness of acupuncture itself.

A new study, involving 401 migraine and chronic headache sufferers, suggests that acupuncture is more therapeutic than standard care. The group was split, with half given 12 acupuncture treatments over three months and the rest were treated by their doctor, and were given drugs when needed.

But after 12 months, the acupuncture group had less severe headaches, had 22 fewer days of headaches, used far less medication, made fewer visits to the doctor for their headaches, and had fewer days off work sick.

The new study, by Andrew Vickers at the Sloan-Kettering Cancer Center in New York, endorses earlier ones, but it can be regarded as the most rigorous and scientific yet undertaken. A Cochrane review of 26 previous studies also concluded that acupuncture was a valuable therapy, but was concerned about the quality of the studies.

More than 10 per cent of doctors in the UK regularly practise acupuncture themselves, or refer a patient for acupuncture, so this latest study will only encourage more to do so.

While we're delighted to see the evidence that acupuncture works, it leaves an awkward question hanging. Is the Western view of the human body completely wrong, and has our medicine been working with the wrong paradigm? It may be the case.

So where did you say you were going to buy lunch?

(Source: British Medical Journal, 2004; 328: 744-7).