The proverbial pain in the neck affects 30% of all men and 50% of all women at least once in their lifetime. Many of us have it regularly and some suffer constantly. Thus neck pain is not just a misery for those who are afflicted by it, it also causes huge expense to all of us, for example through days off work and cost for treatments.

Unless there is a specific cause, such as an injury, neck pain is usually due to two factors: age and an unhealthy lifestyle. As we grow older, our bones and the surrounding tissues in the neck degenerate. Most people's lives do not allow them to do enough exercise, and they spend far too much time in postures which put a constant strain on the neck, such as sitting in front of a computer for much of the day. Both factors in combination mean that neck pain, after the age of 40 or 50, becomes more the rule than the exception. Experts often call this non-specific neck pain.

Treatments for neck pain are numerous: painkillers, spinal manipulation, massage, exercises, heat packs, cupping, traction - you name it, some healthcare practitioners will offer it. Whenever there are dozens of treatment options, there is, I think, good reason to suspect that none is truly effective.

In an attempt to find out what really works, British physiotherapists conducted a rigorous clinical trial. The results have just been published in the journal Arthritis & Rheumatism. The researchers recruited 350 patients suffering from non-specific neck pain. These patients were treated in three different ways. Those in the first group received individually tailored advice and were taught simple exercises which they were advised to do regularly at home. The advice was along the following lines: neck pain is common and not a reason to worry, it is normally not due to a serious disease; rest does more harm than good, so staying active is important. The second group received the same advice plus regular treatments with spinal manipulation of the neck. This approach is often used by chiropractors and osteopaths but, in this case, the treatment was carried out by physiotherapists. Up to eight such sessions of manual therapy were given.

The third group received pulsed shortwave therapy. This is a treatment often used in physiotherapy departments and simply means that mild heat is applied to the painful area in the hope that the warmth will relax the tense muscles and ease the pain.

After the treatments were completed, the success of each approach was evaluated. The primary outcome measure was a questionnaire which quantified the degree of disability experienced by patients through neck pain in daily life. The results were revealing: there was marked improvement in all three groups, but very few differences emerged between them. If anything, the patients who only had the advice and did their own exercises fared best. These patients also used fewer painkillers or other drugs and consulted their GPs less. Half a year later, the patients were reinvestigated. At that point, little had changed; the group of patients who had received advice and kept active still had the best results.

These findings are important. They show that the best options for neck pain are fairly simple and inexpensive. Adding spinal manipulation to the regimen not only does not improve the situation, it may be detrimental. For one, it increases expenditure. As neck pain is such a common complaint, these costs accumulate and would amount to huge sums across the UK. But there is more; while exercise is almost entirely risk-free, other treatments are not. Spinal manipulation has been repeatedly associated with serious complications such as stroke or death. And, of course, painkillers are not risk-free either. They can lead to gastro-intestinal bleeding, damage the kidneys, and perhaps even increase the risk of cardiovascular disease.

So, for once, the cheapest treatment seems to be the best. That must be music to the ears of those who have the difficult task of watching over our healthcare budgets. But there is still one problem: many patients can't be bothered with exercise. It is important that patients are monitored and motivated, ideally by a good physiotherapist who can also check that the exercises are done correctly. As with everything else in life, good intentions are not enough, and only doing things right leads to the right things.

· Edzard Ernst is professor of complementary medicine at the Peninsula medical school at the universities of Exeter and Plymouth.