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Dr Henry Oakeley (above) at the New Medicinal Garden, TCD, marking 300 years of Botany at the college. Below (from left): St Johns Wort, deadly nightshade and liverwort. Photographs: Cyril Byrne, Thinkstock Let me preface this article by saying that I have been waiting for someone to do this for years. I am so sick of all the nature-paths claiming that modern medicine does not take “holistic” approaches, and that natural remedies are the answer. Finally, as elucidated by an expert, we will see that most of these claimed “herbal medicines” are largely myths, perpetuated by the placebo effect.

Herbal remedies don’t cure cancer, homeopathy doesn’t cure anything, plant roots won’t save your life, and botany does not substitute for a M.D.

Plants have been trying to kill us, not cure us, says Dr. Henry Oakeley, the garden fellow at London’s Royal College of Physicians.

The Herbal Fallacies

What the good doctor is going to hit on is the tendency for people to make two serious errors in logic. First, the naturalistic fallacy: this is the idea that something, in this case medicine, is better than any alternative because it is more natural. For medicine this implies more safety, less side-effects, etc. But just because something is natural does not necessarily mean that it is more effective or better for you, if you think it is, you need the evidence to back it up (something that is chronically lacking in the “alternative medicine” scene).

Secondly, people tend to make what I am calling the tradition fallacy. This is where people give weight to an idea just because the idea has been around for a long time, or used for a long time, regardless of evidence of efficacy. As we will see below, many of the claimed benefits to herbal medicine fall into this category, where efficacy is assumed and clinical testing is non-existent.

The Expert

But if plants are, for the most part, as medicinally useless as Dr. Henry Oakeley believes, how does he explain their centrality to the beliefs and practices of medical practitioners for centuries?

Because they believed in the tooth fairy. They had no concept of illness or of chemistry or biochemistry. They believed all plants had been put on the earth by the creator for mankind’s use. So if the plant had a particular shape, it indicated that the creator had put it on the planet for a particular use.

Citing as an example the use of blue liverwort, Hepatica nobilis , once cultivated as a liver tonic because its three-lobed leaf form mirrored the shape of the liver, he says,

It was absolute rubbish. They had no idea how the body worked.”

Pretty, but not much beyond placebo.

And what did you expect? What is more likely, that older civilizations fortuitously stumbled upon miraculous cures that still work better than modern medicine, or that they simply treated any positive outcome (placebo) as valid, and perpetuated it? With no real knowledge of illness or chemistry, there is simply very little chance that these herbal remedies worked in the way they once thought. Today, we know that they hardly work at all.

He goes on:

The basic concept that most people have missed is that many plants are poisonous,” he says. “We just have to find a way of using the poisons in plants to our advantage.

While early doctors may have had little concept of how things worked in the body, the effects of plants on the brain were more observable, for example with opium for pain-killing effects, or small doses of night-shade for anesthesia.

However, Oakeley dismisses suggestions of belladonna’s efficacy as a modern-day homeopathic remedy. He says the fact that a plant may have been used in medicines for thousands of years doesn’t lend such claims any more weight (which is an adaptation of our tradition fallacy).

Then, in a wonderful bout of scientific skepticism, he adds:

“In most cases it’s been a myth from day one,” he says. “Homeopathic medicine is a complete fairy tale. To a put a molecule of a chemical into gallons of water: there’s no reason why it should work. The only response you get from homeopathic medicines is a placebo response.”

An actual tweet from a homeopath. Let's just say that he's lacking in the logic department.

Using an example of the efficacy of herbal remedies, he adds that roots hung around the neck were regarded as a cure for epilepsy by Galen as far back as AD 200, with the plant cropping up again in a 1737 book called A Curious Herbal as a cure for febrile fits in teething children.

‘Nailing a brick to a wall would have been just as effective,’ he remarks. ‘Febrile fits are self-limiting and will stop when the fever subsides anyway.’

In short, many of the supposed effects produced by these remedies aren’t effects at all, they are natural responses that a body would take even without any herbs. Many herbal remedies persist today because of just these types of misunderstandings. It really is a superstitious belief at best; if a child stops seizing when there happens to be a root around his neck, people kept doing it, independent of knowing whether the root had any effect at all.

[Think of any sports-related superstition, like bouncing the ball exactly four times before shooting a free-throw. The bouncing had nothing to do with it, but your brain makes the connection regardless of proof, and you will continue that little superstition.]

However, he concedes that some plants used by the ancients did have curative properties – and continue to have a place in medicine today. Used in Egypt for centuries to treat renal colic, khellin, a member of the cow parsley family, was found in the 1920s to cause dilation of the urethra and the coronary arteries. As a result of the discovery, drugs have been developed that treat angina and cardiac arrhythmias today. A 16th-century GP William Withering found that a patient of his was cured of dropsy (heart failure) after taking foxglove leaf prescribed by a herbalist. A chemical extracted from foxglove leaf is now the source of the modern-day cardiac medicine digoxin. A more recent example is the plant Chinese star anise, the seedpods of which are used to make shikimic acid from which Tamiflu, the treatment for bird and swine flu, is made.

But remember, these medicines are merely chemical evolutions of some of these herbs, and they are not by themselves medicine. The beneficial qualities had to be chemically extracted in ways that were impossible for previous generations to accomplish. Make note that this chemical extraction would not fit into the definition of a “natural” or “herbal” remedy.

Conclusions

As Dr. Henry Oakeley points out, the number of plants that have evolved from herbal medicine to real medicine is tiny:

The thousands of years of plants being used as medicines have actually taught us very little.

Welcoming forthcoming UK legislation that will be stricter on the prescription of herbal medicines, he says the claims by some that they have fewer side effects are misleading. St John’s Wort, for example, a herbal remedy used for depression, can work by blocking the destruction of serotonin, he says – and side effects include the possible inactivation of the heart drug warfarin, oral contraceptives and HIV treatments.

Herbalists say these things are pure and don’t have the same side effects as something like Prozac, but they have other side effects . . . That’s the problem with herbal medicine, there is no proper long-term check on the side effects.

And this of course is the root of the problem (pun!): there are not proper checks in place to keep the pseudoscience of the useless herbal remedies out of medicine. If listed as “supplements”, for example, the requirements that need to be met to get sold on store shelves shrinks considerably. Just look at how many pharmacies sell homeopathic medicine.

People have faith in herbal medicine and if you have faith in something then it has an effect. The only thing wrong with herbal medicine is that it may have a side effect. Also, you may not be treating the illness.

Opposed to this is the beauty of modern medicine. The checks, the trials, the tests, the evidence, the science; it all lines up to give humans an actual fighting chance against the many illnesses that plague us. Modern medicine is not hampered by fallacies or supposed effects; it is supported by mountains of scientific knowledge. Biology, physiology, chemistry; each field has contributed to, and confirmed our knowledge about medicine. Where “natural” medicine fails, is that it is, in fact, not supported in the ways proponents claim, by any of this.

Going Forward

Oakeley is also cognizant of the fact that his own view of medicine also represents a moment in time.

In 60 years’ time, our current medicines will seem as rudimentary as peony root . . . just as we currently treat pneumonia by treating the bacteria that causes it, we will treat diseases like cystic fibrosis, schizophrenia and Alzheimer’s by treating the gene which causes them.

Let’s hope so.


[Update]

New EU rules came into force recently, banning hundreds of herbal remedies. The laws are aimed at protecting consumers from potentially damaging “traditional” medicines. Under the directive, herbal medicines will now have to be registered. Products must meet safety, quality and manufacturing standards, and come with information outlining possible side-effects.

Research conducted for the Medicines and Healthcare Products Regulatory Agency (MHRA) in 2009 showed that 26% of adults in the UK had taken a herbal medicine in the last two years, mostly bought over the counter in health food shops and pharmacies.

The agency said it hoped to promote a more cautious approach to the use of herbal medicines after a study found that 58% of respondents believed these products were safe because they are “natural” [The Naturalistic Fallacy, see above]. In fact, herbal remedies can have harmful side-effects.

St John’s Wort can stop the contraceptive pill working, while ginkgo and ginseng are known to interfere with the blood-thinning drug warfarin. And in February the MHRA issued a warning about the herbal weight loss product Herbal Flos Lonicerae (Herbal Xenicol) Natural Weight Loss Formula, after tests showed it contained more than twice the prescribed dose of a banned substance.

From now, manufacturers will have to prove their products have been made to strict standards and contain a consistent and clearly marked dose. Remedies already on sale will be allowed to stay on the shelves until their expiry date. The agency said there had been 211 applications for approval of herbal remedies so far, with 105 granted and the rest still under consideration. Approved remedies will come with a logo marked THR.

Let’s hope that America takes notice of these kinds of measures to protect consumers from pseudoscience.

[Via the Guardian]


For more information on Dr. Oakeley and his views, click here.