Dear Readers,
I’ve written previously about the unregulated and potentially dangerous nature of the supplement industry, and also reshared this excellent primer on the subject by Dr. Jen Gunter. Those who follow me on Substack Notes will know that I’ve recently highlighted and debunked some veterinarians on Substack who promote homeopathy (which really grinds my gears to see). And far from a small niche product, homeopathic remedies are a multi-billion dollar industry with many supporters and a powerful lobbying arm 👇
Since most people aren’t familiar with the details of this modality, today I want to discuss:
What exactly is homeopathy and how do its proponents say it works?
What does medical and scientific research say about homeopathy?
How safe (or not) are these remedies?
What IS homeopathy?
When many people hear the word “homeopathic” they think it is simply another term for “natural,” “holistic”, or “herbal” remedies. While some of those remedies are derived from plants, homeopathy itself is a very specific product with a peculiar past and some bizarre beliefs.
In brief, homeopathy is a system of alternative medicine created in 1796 by Samuel Hahnemann based on his doctrine of “like cures like” (similia similibus curentur), a dubious claim that a substance that causes the symptoms of a disease in healthy people would cure similar symptoms in sick people. Right away, you should be questioning this idea because frankly, it doesn’t make a lick of sense. For example, the old-timey way to induce vomiting when poisoned was to drink syrup of ipecac to make you puke, but if you give this to someone with gastritis, far from curing them, it will very much worsen their condition and probably land them in the hospital.
Many homeopathic remedies are derived from literal toxins like arsenic or lead 😬 But don’t worry! The second principle of homeopathy is “the law of minimum dose” that says the lower the dose, the more effective the medicine, and during the manufacturing the original substance is progressively diluted thousands or millions of times (hilariously called “potentization”) with alcohol or distilled water and then vigorously shaken in a process called “succussion.” In fact, typical remedies are so dilute you would not find a single molecule of the original substance in the liquid!
Finally, you may be asking yourself: If these “remedies” are so dilute that not a single molecule is left in it, how in the world would the remedy work? Proponents of homeopathy believe in a pseudoscientific concept called “water memory,” whereby—through unclear mechanisms—water “remembers” what it was previously exposed to! To put it simply, this conflicts with all known laws of biology, chemistry, and physics. It is also gross: if true, this would mean every time you drank a glass of water it would be filled with the “remembered energy” of 💩 from water we purify from the sewer system 🤢🤮
Dr. Steve Novella (a neurologist at Yale) sums up the issue well in this article:
“I would like people to be aware of the fact that homeopathy is a pre-scientific philosophy, that it is based entirely on magical thinking and is out of step with the last 200 years of science. People should know that typical homeopathic remedies are diluted to the point that no active ingredient remains, and that homeopaths invoke mysterious vibrations or implausible and highly fanciful water chemistry. I would further like people to know that clinical research with homeopathic remedies, when taken as a whole, show no effect for any such remedy.”
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What does the science say?
It is very clear: The overwhelming majority of individual studies evaluating homeopathy show there is no evidence they work beyond a placebo effect, and the overall amount and quality of research for them is poor in general. There are probably a few studies out there suggesting some benefit, but these are virtually all methodologically flawed and handicapped by bias (performed and/or sponsored by people who financially benefit from homeopathy). Furthermore, it is not unexpected to see occasional studies with outlier results, which is why we perform meta-analyses (pooling results from multiple studies) and systematic reviews—these follow a predefined, transparent, and rigorous methodology to collect, evaluate, and synthesize findings from multiple studies, including meta-analyses.
The Cochrane organization is a non-profit research organization in the UK that performs systematic reviews of all kinds medical tests and treatments. To date they have performed EIGHT separate systematic analyses of homeopathy for different uses ranging from irritable bowel syndrome to asthma and hormonal symptoms and all found similar conclusions:
Homeopathy for ADHD:
“Overall the results of this review found no evidence of effectiveness for homeopathy for the global symptoms, core symptoms or related outcomes of attention deficit/hyperactivity disorder.”
Homeopathy for chronic asthma:
“The review of trials found that the type of homeopathy varied between the studies, that the study designs used in the trials were varied and that no strong evidence existed that usual forms of homeopathy for asthma are effective.”
Homeopathy for Irritable Bowel Syndrome:
“The results for the outcomes assessed in this review are uncertain. Thus no firm conclusions regarding the effectiveness and safety of homeopathy for the treatment of IBS can be drawn.”
Homeopathy for acute respiratory infections in children:
“We found no evidence to support the efficacy of homeopathic medicinal products for ARTIs in children. Adverse events were poorly reported, and we could not draw conclusions regarding safety.”
Homeopathy for reducing hot flashes:
“In the studies on non-pharmacological therapies, relaxation therapy was the only one that probably reduced the frequency and severity of hot flushes. Homeopathy, acupuncture and magnetic therapy may not lead to any differences in the number and severity of hot flushes.”
Homeopathy for inducing labor:
“The review of two trials, involving 133 women, found there was not enough evidence to show the effect of a homoeopathy as a method of induction.”
Homeopathy for dementia:
“The researchers did not find any good quality trials and so cannot say whether it is or is not effective for treating this condition. As no information is available on how much homeopathy is used for dementia, it is difficult to say whether it is important to conduct more trials.”
Homeopathy for bed wetting in children:
“There was weak evidence to support the use of hypnosis, psychotherapy, acupuncture, chiropractic and medicinal herbs but it was provided in each case by single small trials, some of dubious methodological rigour. Robust randomised trials are required with efficacy, cost-effectiveness and adverse effects clearly reported.”
If this doesn’t beat the dead horse enough for you, you can explore the >100 studies in PubMed using this search criteria:
(homeopathy[Title/Abstract]) AND (systematic review[Title/Abstract])
What are the potential harms of homeopathy?
First, it can delay or replace proper testing and treatment. My first job with animals was early in college working for a facility that trained dogs to help the hearing impaired and people with seizures. The owner and trainers were heavy into homeopathy and alternative treatments, and very skeptical of traditional veterinary medicine. Part of my responsibilities was walking, feeding and medicating these wonderful animals. Sadly, I watched numerous dogs with serious ailments like heart failure waste away and die because they were given homeopathic remedies in place of standard medications like lasix. Obviously this was traumatic and I left the job because of it. That experience undoubtedly made me passionate in my stance about homeopathy, but it doesn’t change the facts described above.
Second, it costs money, which is a limited resource that could be applied to real medical care. My blood boils when I see pets come in treated for a long time with homeopathy or other nonsense and when we're finally able to diagnose the real problem (often cancer or a chronic inflammatory condition or degenerative heart/kidney disease) they are out of money and can't go further with a care plan 🤬
Finally, because alternative therapies are totally unregulated in the US, there is the very real risk of adulteration or improper diluting of their “remedies.” One FDA investigation found:
“The products in question contain mercury, lead, strychnine, and deadly nightshade. Diluting horrible toxins to negligible levels is standard homeopathic practice, so that in itself is not new. But the FDA found that these substances were present in wildly variable doses in tested product, and in some cases in potentially toxic doses. The four companies have 15 days to alter their practices or the FDA will take further action.” (Source)
In conclusion:
Homeopathy is not simply a catch-all term for “natural” or “herbal”
It is fundamentally based on pseudoscientific principles
Rigorous research shows it does not work beyond a placebo effect
It can waste time and money
The lack of regulation around supplements means there is a risk of adulteration
I hope this was a useful primer on the ins and outs of homeopathy. Please let me know what questions you have in the comments, or shoot me an email at:
Quite a shame that so many studies have been done on an inherently implausible treatment theory that Cochrane can crank out multiple meta-analyses to disprove what is self-evidently nonsense.
Good to keep educating people and flooding the zone with reason, as the zone is saturated with these money making placebos. And placebos do “work” up to 30% of the time for some “symptoms”, but like you said, for serious illnesses undiagnosed or left untreated this becomes unethical and very dangerous.
Tim Minchin summed it up perfectly: "do you know what they call alternative medicine that has been proved to work? ... Medicine."