Many CAM therapies have little scientific backing. For example, although some acupuncture studies have revealed that it is effective for specific conditions, there still remains uncertainty about other uses, and much debate revolves around acupuncture’s mechanism of action (British Medical Association, 2000). Rather than rejecting these approaches, these challenges should stimulate the ingenuity and inquisitiveness of scientists to find adequate control therapies. Also included in this category are most herbal medicines. Hundreds of plant species are used in thousands of products with different formulations. Yet very few have been clinically tested. This is a huge potential resource for medicine, since more than half of the most prescribed drugs in the US were discovered in nature or are based on natural products (Newman et al., 2000). The anticancer agent taxol (paclitaxel), for instance, was initially isolated from the yew tree (Taxus brevifolia) by systematic testing of plants by the US Department of Agriculture for the National Cancer Institute. Scientific testing of these unproven CAM therapies is obviously necessary for safety reasons too. While clinical studies reveal that the herb St John’s wort is effective for relieving mild to moderate depression, other studies show that its active ingredients interfere with the metabolism of other drugs (Moore et al., 2000) such as cyclosporin and oral contraceptives.

This second category of CAM also has little scientific support, but these therapies are also based on principles or theories that contradict well-established scientific knowledge. Homeopathy is a good example, where dilution with shaking, even to the point of diluting out every molecule of original ‘active’ ingredient, is believed to increase the pharmacological potency of a solution. While proponents claim homeopathy is extremely effective, two-thirds of Americans found it of little or no help (Consumer Reports, 2000); the remaining one-third who said the treatment helped ‘much’ could well have been benefiting from the placebo effect. Although a 1997 review in The Lancet initially found that the placebo effect could not explain all of homeopathy’s reported benefits, the researchers later revisited their data and concluded differently (Linde et al., 1999). They found a correlation between the results and the quality of studies, with low-quality studies tending to find homeopathy more effective. These findings are to be expected when therapies are alleged to work by questionable mechanisms, and scientists are justified in remaining sceptical of these approaches.

Although defined in different ways, the term quackery comes from ‘quacksalver’, originally applied to untrained persons practising medicine. People who promote quackery generally believe their therapies work, but they do not have enough training to know that their effectiveness is highly unlikely. In contrast, those who promote fraudulent therapies know they are not effective, but they deceive people for profit. Unfortunately, quackery and fraud can occur throughout medicine. But they thrive more easily in an environment where therapies are not expected to have scientific support or where the medical establishment is excessively mistrusted. These therapies often make extravagant claims or disguise themselves in pseudo-scientific language. For example, ‘Vitamin O’ is promoted in the US as having many health benefits. The manufacturers claimed that scientists in the space programme developed a product that contains ‘O4 or two O2 molecules joined together in a very stable bond’ by using ‘breakthrough quantum physics technology’. They later paid a large fine to the US Federal Trade Commission, the agency responsible for monitoring truth in advertising (www.ftc.gov/opa/2000/05/rosecreek2.htm). However, Vitamin O remains on the market, promoted now by testimonials. To help people spot quackery and fraud, scientists must become involved in public education. Only when people become convinced of the importance of scientific testing and critical thinking will the waste of resources spent on quackery and fraud be prevented.

This is a collection of diverse practices based on the alleged existence of a non-physical force called prana, chi, ka or orgone. This life-energy animates the human body as it is transformed into matter and physical energy through channels called chakras. Since it is non-physical, no instruments can detect or measure it. In this perspective, illness, ageing and death result from imbalances or blockages in the flow of life-energy; healing is achieved by re-balancing its flow through the body. Meditation is a central aspect of energy medicine, as it trains people to sensitise themselves to detect life-energy and to manipulate it. Best-selling authors (e.g. Deepak Chopra, Larry Dossey and Carolyn Myss) devote their books to these ideas. Energy medicine is at the core of many traditional forms of alternative medicine, such as Chinese and Ayurvedic medicine. Practices such as therapeutic touch, Reiki, qigong and tai chi are based exclusively on these principles. Some claim acupuncture, chiropractic, herbal remedies and homeopathy influence this life-energy, although other practitioners claim these practices have a purely physical mechanism of action. Questions of effectiveness and safety must be addressed here, but so too must the fact that spiritual and religious teachings are often presented in the guise of therapy. When health-care professionals offer or promote energy medicine, they should openly declare that this is based on ancient religious teaching and not on professional training. Barnum (1996) surveyed the popularity of these therapies among US nurses and commented, ‘Is the practice of the New Age nurse deceptive? Do patients’ weakened conditions simply make them targets of opportunity? If New Age nursing is care of the soul, is it also usurping the field of those perceived to be more prepared for that task, namely, religious priests, ministers, and rabbis? Or is the nurse a representative of a new religion?’

This final category includes much of what is actually beneficial. Almost every popular CAM book includes extensive discussions on nutrition, exercise, stress reduction, relationships, spirituality and other lifestyle issues. Common sense and mounting evidence from studies show that these factors are indeed important in preventing and recovering from illness. The successes of conventional medicine led some patients to believe medicine could fix every health problem. People ran their bodies into the ground, and then turned to the doctor to repair them. But during the last decade or two, people have realised that this does not work and are becoming more interested in taking responsibility for their health to prevent problems that later require powerful drugs or extensive surgery. Sir William Osler, the great physician and professor of medicine, valued both, science and holism (Osler, 1932). In 1901 he declared, ‘A new school of practitioners has arisen which cares nothing for homeopathy and less for so-called allopathy. It seeks to study, rationally and scientifically, the action of drugs, old and new. It is more concerned that a physician shall know how to apply the few great medicines which all have to use, such as quinine, iron, mercury, iodide of potassium, opium and digitalis, than that he should employ a multiplicity of remedies the action of which is extremely doubtful.’ Osler then continued, ‘Perhaps in no particular does Nineteenth-Century practice differ from that of the preceding centuries more than in the greater attention which is given to the personal comfort of the patient and to all the accessories comprised in the art of nursing’. These two principles form the foundation of every good therapy, whether conventional or alternative.

The history of medicine paints terrible pictures of medicine without science. Patients were bled and given poisonous concoctions, often on the sole basis of anecdotal reputations. Today, all therapies used in conventional medicine must undergo thorough testing before they are approved using the randomised controlled trial (RCT) as the gold standard of scientific studies. But these studies often work as well with CAM therapies, and many aspects of the RCT were in fact developed with what today would be called CAM therapies. One of the earliest studies to compare groups of similar patients was James Lind’s research that identified the value of citrus fruits in preventing and treating scurvy (Mellinkoff, 1995). Later, the ‘blinding’ of patients was introduced by Benjamin Franklin and his investigators to test the efficacy of animal magnetism, and then refined throughout the 19th Century in testing homeopathic remedies (Kaptchuk, 1998).