June 14th – 21st 2010 [and 2012] is the UK homeopathy awareness week, so I thought it might be a good idea to try and raise awareness of homeopathy.

Cinchona

Homeopathy is based on the principle of similia similibus curantur (likes are cured by likes). The hypothesis is that symptoms of illness are caused by a derangement of the ‘vital force‘ assumed to be present in a living organism and substances which elicit the same derangement (i.e. symptoms) will rid the body of the illness. This was originally identified in the context of homeopathy by Hahnemann with reference to cinchona bark (source of quinine) and malaria. The previous proposed mechanism of effectiveness of quinine against malaria was its bitterness, but Hahnemann sensibly identified that other bitter substances did not offer the same protection. Instead, after taking cinchona and experiencing a reaction similar to the reaction he associated with malaria, he hypothesised that it was this similarity in symptoms that made cinchona bark effective.

Modern homeopaths still use a similar method to identify their treatments. When in a healthy state they try a preparation and keep a detailed diary of any effects that they feel the treatment has on them. This is called ‘proving’ although what it is supposed to prove is hard to determine since there are no rigorous controls in place and the results are not statistically tested to see if they are anything other than random. Consider the perceived effects of taking peregrine falcon blood for example:

Short statement on peregrine falcons:

The Peregrine Falcon is widely renowned for its incredible speed. Estimates vary, but commonly cited top velocities are in the range of 290-320 km/h (180-200 mph), achieved only during the characteristic swoop (hunting dive)…the Peregrine Falcon is the fastest creature on earth.

Observation during proving:

‘Drove back from the party (had some wine but not so much) quite fast but well, changing speed as necessary. It seemed faster to the others in the car than to me.’

I heartily recommend reading the entire page about the proving of peregrine falcon blood – it is an education into how homeopaths derive their information about the treatments they prescribe (and it is ludicrous to the point of hilarity). Is this really a rigorous approach to testing healthcare products or is this more about symbolism, appeal to the mystical and delusion?

Evidence based medicine occasionally does use elements of  similia similbus curantur such as with inoculation and vaccination – where a small or denatured dose of a disease causing agent is introduced with the intent of stimulating an autoimmune response that will prevent the full blown disease from becoming established should the person come into contact with a large active dose of the pathogen.

Foxglove

Also, many physiologically active compounds have medicinal uses because they act on particular organs and metabolic pathways via a biochemical route that can have apparent similarities to the illness being treated. For example, digoxin is a cardiac glycoside found in foxgloves that decreases heart rate and increases force of heart contraction – fatal in large doses, but useful for treating atrial fibrillation in small doses – so at a very gross level this could be considered ‘like treating (rather than curing) like’. It is also vaguely plausible that a substance which elicits a physiological response which mimics symptoms of an illness that arise as part of the body’s  immune response (such as raising temperature) may have the effect of fighting an infection (although I have not seen any evidence for this).

Hahnemann’s experience with cinchona happened in 1790 when the medical community of the time was still dominated by the miasma theory and humourism of the Middle Ages. Vitalism was a standard of the medical profession at the time, with good health being dependent on balancing the four vital humours. The idea of a biochemical autoimmune system did not take shape until a century later, but when it did it revolutionised the medical field, bringing about treatments with previously unprecedented success (eradication of smallpox anyone?). Hahnemann had no idea about the mechanism by which the body actually heals itself, he also had no idea that malaria was not caused by a miasma, but by a microscopic parasitic protist of the genus Plasmodium.

Plasmodium falciparum – the protozoan that causes malaria

In short Hahnemann was trying to fit his limited observations into a theoretical framework consistent with the body of assumed knowledge available at the time. The same way that scientists have always worked. However, over time the body of knowledge has changed – vitalism has been rejected as evidence has been amassed which demonstrates that all of the functions historically proposed for vital energy are demonstrably biochemical in nature. Disease is now well recognised as being caused by bacteria, viruses, proteins and biochemical abnormalities rather than by derangement of ‘vital energy’. The idea of a vitalistic treatment for a biochemical problem seems rather at odds with the facts, particularly since there is no evidence to suggest that vital energy even exists. Sticking with malaria, we now know that the antimalarial component of cinchona is quinine, which is no longer effective as an antimalarial due to the resistance evolved by Plasmodium – how such immunity might have evolved in response to vital energy is hard to fathom.

Homeopathy also subscribes to the principle that the smaller the dose, the more effective it is at influencing the vital energy – to the point where homeopathic remedies are diluted until they no longer contain even one molecule of their active ingredient. Indeed it would take a ball of water the size of the solar system to contain one molecule of active ingredient in the more ‘potent’ homeopathic remedies – making them even less tangible than the Emperor’s new clothes. Of course this idea of smaller doses having a bigger effect flies in the face of everything that is demonstrated in evidence based medicine, where dose dependent effects increase with increasing dose size, through a therapeutic window until a plateau is reached or there is an overdose.  The Ten23 campaign was all about this misplaced faith in super-dilution.

If homeopaths were able to demonstrate that vital energy exists then homeopathy might have a theoretical leg to stand on, as would chiropractic and a suite of Ayruvedic medicines, but without any evidence for vital energy they remain theoretically unfounded. Interestingly, mainstream medicine was once based on the concept of vital energy, which has only been discarded due to improvements in experimental methods. Vital energy is one of those strange forces in nature that becomes harder to see the harder you look for it – probably because it only exists as a cultural concept that has no relevance in the physical world. This erosion of evidence for vital energy not only leaves homeopathic theory unfounded, but necessarily rejected.

Headstone for 9 month-old girl who died because her parents chose homeopathy over conventional treatments

Theory aside, if there was strong evidence for efficacy of homeopathic remedies then there would be very good reason to question the laws of physics and our current understanding of biology and medicine. However, there is no persuasive evidence for homeopathy’s efficacy. As such it seems bizarre that people still hold on to this outdated and superseded faith-based system of medicine; but then again there are still Flat Earthers, Faith healers and people who drink their own pee, so I suppose it’s no great surprise. There are dangers however – if people choose to use homeopathy in place of medicines that have evidence of efficacy, they run the risk of harm or even death – and I think that’s something everyone should be aware of.