It’s one of medicine’s most hotly-debated topics – can ‘the memory of water’ really hold the cure to healing the body? Alan Coughlan investigates the controversial world of homeopathyIt’s often said that ‘what doesn’t kill you makes you stronger’. In practice this is a mantra for life’s struggles, and it is this guiding principle that underlies a type of medicine that defies the laws of science.The first of the two guiding principles of homeopathy is the concept that ‘like cures like’. First formulated in the 18th century, homeopaths attempted to cure hayfever by using a substance which causes the same runny nose and watering eyes as an allergy to pollen. It was allium separ: more commonly known as onion. The modern list of substances administered ranges from the simple to the absolute bizarre. Nylon, red spider venom, deadly nightshade, chalk, snake venom… even the tuberculosis gland of a cow has been used in homeopathic remedies. Something that was quickly noticed in administering these substances, though, was that some of them were highly poisonous.This brings us to the second guiding principle of homeopathy, serial dilution – the idea being that the more you dilute a substance the more effective it becomes, provided it is done in a special way. 1ml of a liquid is dissolved in 99ml of water, violently shaken and hit against a hard surface (an action all homeopaths regard as essential). This is known as a ‘1C’ solution. 1ml of this is now dissolved in another 99 drops of water to make a ‘2C’ solution.It is here that the real clash with science begins. At 6C, the medicine has been diluted a million million times – the equivalent to one drop in twenty swimming pools. 12C is equivalent to one drop in the Atlantic Ocean. However, a typical homeopathic solution has been diluted 30C – less concentrated than a single drop in all the oceans of the world. Homeopaths believe that one drop of this solution is sufficient.Science, understandably, has a problem with this, suggesting that one can only dilute a solution to the point where only one molecule of the original substance remains. According to research chemist Walter Stewart, there is less than a one-in-a-billion chance that one molecule would remain in a homeopathic solution. For a medicine to have an effect on the human body, there must be a sufficient quantity of an active ingredient. Thus, if there’s not even a trace of the original substance, there can be no reaction.In the 1980s, one of the big names in French science was Jacques Benveniste. With a string of discoveries to his credit, many felt he was on his way to a Nobel prize. It was in his research into allergies whilst working with basophils – a white blood cell involved in allergic reactions – that he made a discovery which ultimately ruined his career. When a person comes into contact with a substance to which they are allergic, basophils become active, causing the telltale symptoms of a runny nose and itchy eyes. Benveniste devised a test using a dye that turned inactive basophils blue. One of his technicians, however, noticed that a solution which had been diluted homeopathic levels was activating the cells. Benveniste was suspicious, and so set about conducting hundreds of experiments, at the end of which he declared to have discovered a ‘special’ kind of water that seemed to be remembering the substance it had once contained. He called the phenomenon ‘the memory of water’.This was the evidence the homeopaths needed, and Benveniste knew it as he sent his results to Sir John Maddox at scientific journal Nature, who agreed to publish them if Nature could come and inspect the lab. Nature found, in due course, the same results as the ‘memory of water’ predicted. One of the Nature team noticed, however, that Benveniste’s technicians knew which tubes contained homeopathic water and which didn’t, and suspected that this knowledge might be influencing the results. The experiment was repeated blind, where nobody would know what tubes contained what kind of water, and with each tube labelled by a secret code. When the experiment was concluded and the code was cracked, it became clear that the special water was having no effect at all. Benveniste was criticised at large for not applying scientific methods as rigorously as he should, and his reputation was ruined.Homeopathy has been shown in the lab, time after time, not to work – so why do millions of people use it? The answer may lie with the placebo effect. Doctors have known for a long time that people can be cured with pills containing nothing more than sugar. Bizarrely large pills can work better than small ones, and coloured better than white pills. The key is that the patient believes the pill will help them. This belief is enough to lower the production of stress hormones, with the physiological effect is to feel better.Another stage in the application of homeopathy may use this effect: the consultation. A homeopath will, before creating a medicine, sit down and talk with their client. Everything is discussed, from eating habits and sleep patterns to tension in their lives, and advice is even given on how to lower stress levels.On the face of it, the evidence seems to refute the possibility that homeopaths produce anything more than water – and an explanation for the effects of the medicine has not been given by either side. Dr Stephen Novella, a neurologist, says that “homeopaths target the worried well who have self-limiting or chronic symptoms – things that don’t need real medicine,” and points to an anonymous online quote to explain the public’s use of this particular alternative medicine.“It’s curious that with low grade chronic conditions, like back pain, seasonal affective disorder etc, that people are eager to try alternative hocus pocus – but bring on something virulent, acute and truly terrifying, and roll on Western medicine. Nothing like your eyeballs leaking blood to bring things into perspective.”