(Investigator 171, 2016 November)


In the absence of information or empirical evidence, the beneficial or deleterious effects of herb ingestion could only be discovered by trial and error and by observing the effects on birds and animals. One can only speculate on what the cost in human terms must have been before it could be determined what was and what was not safe to eat.

A considerable mythology has arisen around herbs, in particular, the doctrine of signatures — the principle that the external characteristics (such as shape) of a plant, animal, or other entity signal its magical or healing properties and that relationships exist between the appearance of a source of medicine and the diseases against which it is effective. For example, the Pulmonaria plant, with its speckled leaves resembling the lungs, was considered appropriate as a remedy for lung disease, and a ginseng root in the crude shape of a human male was considered to be an aphrodisiac. It was also a medieval belief that a beneficent creator would not expose us to ills without also supplying remedies. In reality of course, the chemicals in plants have evolved as a defence against predators, not for our purposes.

With the invention of written language, the results of experience could be recorded and evaluated for future reference. We know from clay tablets, written in cuneiform, that the Sumerians used licorice, mustard, opium and thyme for medicines, and that the Egyptian Ebers Papyrus of about 1500 BC, listed more than one hundred and twenty-five plants as well as hundreds of prescriptions for disease and accidents. Earlier, the Chinese recorded a materia medica, the Shen Nung Ben Tsao, which listed more than three hundred medicines, and a revised edition was published in 659 AD., the work of some two thousand scholars.

In 1578, Li Shih-chen, possibly China's greatest naturalist, published his Ben Tsao Kung Mu, or the Chinese Pharmacopoeia. This magnum opus listed over one thousand botanical species and a similar number of standard medical prescriptions, many of which are in current use. India too, has its pharmacopoeia of some two thousand plants which form the basis of Ayurvedic medicine.

In 1640, English herbalist John Parkinson produced his massive Theatrum Botanicum — eighteen hundred pages detailing three thousand eight hundred plants, and shortly afterward, Nicholas Culpeper produced his classic work, The Complete Herbal. By the middle of the nineteenth century, in Europe and in the US, almost eighty per cent of medicines were plant derivatives.

Since the 1980s, the health food industry and multilevel marketing companies have aggressively marketed herbal remedies under the guise of "dietary supplements" to evade having their products regulated as drugs. World-wide, vitamins, herbs and supplements are a multi-billion dollar industry with enormous power and political influence.


Why primitive man turned to plants for medicinal purposes is a matter for conjecture. Plant life already provided food, clothing and shelter, why not healing properties? Perhaps it was simply a "medical instinct” — a subconscious awareness that nature has provided.


Plant-based products have been and still are used for a great variety of medicines and preventatives. They take the form of liquids, powders, pastes, balms, aromas, liniments, tinctures, poultices and ointments to be eaten, swallowed, inhaled or applied.


Although herbal medicine has been around for thousands of years, longevity is not necessarily a criterion with which to measure its efficacy.

It is no secret that health hazards from using herbal remedies can range from acute toxicity to insidious, long term effects. In recent years, medical and scientific literature has frequently drawn attention to actual and potential liver damage as a result of using herbs. Two well-known remedies, comfrey and sassafras, fall into this category. However, potential harm attends the use of many other herbal therapies if they are not used appropriately.

Is there sufficient information and adequate controls available to protect individuals? The answer is no. More quality is needed, whether it is provided by practitioners or governments.

A significant percentage of drugs trace their origin to plants. However, very few (almost none) are used in their raw form as drugs. When a plant shows potency, drug companies try to identify and improve on its structure.

There have been many botanical remedies that have worked consistently and effectively to treat many ailments, and many substances derived from plants form the basis of commercial medications for the treatment of such complaints as heart disease, high blood pressure, pain and other problems. Ephredine, an active ingredient in the herb ephreda used by the Chinese for over two thousand years, is currently used in pharmaceutical preparations for the relief of asthma. Digitalis, the powdered leaf of the foxglove plant discovered in 1775, is used as a cardiac stimulant.

There are numerous books on herbalism available, many of them the self-help variety. Although nearly everybody does a certain amount of self-diagnosis and medication, caution is advisable as many herbs are potent substances. It should be noted that herbology and herbalism are terms with no scientific or legal meaning that refer to "the study of herbs".

Any substance capable of exerting a medicinal effect is also capable of producing adverse side-effects. Some of the problems associated with herbal product manufacturing and marketing include:

1. Inadequate information on labels to enable health professionals to make clinical judgments when patients experience problems.
2. Failure to properly identify plant sources used in the product.
3. Failure to standardise dosages and to identify and track batches during production.

There have been an increasing number of reports of harm ensuing from herbal preparations. Serious injuries and deaths have been associated with the use of pennyroyal, ephedra and caffeine combinations, ermanda, chaparral, lobelia, willow bark, stepania, magnolia, yohimbe, comfrey, licorice root and diuretic herbs to mention a few.

Although the public's general perception of herbs is that they are nature's gift to man and being "natural" can do no harm, many of them are highly toxic. Some natural substances can cause cancer and induce tumours. For example, the breast cancer drug, taxol is derived from the bark of the pacific yew tree. The toxicity of the Taxus species is such that in 1993, there were nine hundred and sixty-nine cases in the US alone of human poisonings attributed to yew. Any attempt to categorise herbs as "alternative" "complimentary" or "holistic" would be treading on thin ice. They could well be all three. Consider the following.

Until recently medical doctors have not considered herbal medicine a subject of discussion. Today, most are indifferent, puzzled, or curious. It has been implied that the reason for this is because herbal medicine is taking customers away from the multi-million dollar prescription drug industry which underwrites the very existence of medical associations. This of course, may or may not have an element of truth in it, and although it has been hotly debated, begs the question whether or not the prescribing of herbal preparations should be incorporated into mainstream medicine. However, the same accusation could be levelled at the herbal companies who supply herbal preparations to herbalists, as it too is a multi-billion dollar business. Any hostility by the medical profession is more likely to be the lack of substantiation of the claims made on behalf of herbal medicine. It would appear then that the question has, to a certain extent, already been answered.

To go into any great detail about the pros and cons of herbal medicines would require a book in itself. For the purpose of this assessment therefore, I will confine my comments to one of the more popular products — herbal teas.

A plant produces a wide variety of chemical compounds that can affect the human body — acids, tannins, essential oils, alkaloids and glycosides. Since some alkaloids and glycosides build up in body tissue, it's possible for them to build up to significant levels. From time to time, new evidence of toxicity comes to light causing some long-accepted herbal products to be dropped from the list of those generally accepted as safe products. In recent times, substances derived from the plants calamus, sassafras and the tonka bean were considered safe. Subsequent research determined that they were either toxic or carcinogenic.

People drinking herbal teas expose themselves to thousands of chemicals about which little is known and that have not been subjected to research to determine their safety. Some companies have gone overboard with claims. For example, during the 1980s, Herbalife International received adverse publicity for making illegal claims that various herbal ingredients were effective against more than seventy diseases and conditions. In 1986, Herbalife agreed to pay U5$850,000 and to abide by a long list of court ordered restrictions on claims and marketing practices.

One ingredient in Herbalife's Thermojetics system at that time was the herb ma huang. This herb contains ephedrine, a decongestant that poses risks for individuals with high blood pressure, glaucoma and several other conditions. Canada banned the sale of products containing ephedrine in 1994, and Texas followed suit following reports of several deaths and serious illness among abusers of products containing ephedrine.

Fourteen commercially available herbal teas, including the popular chamomile tea, listed in American Pharmacy, Vol. NS28, No.4, April 1988/231, contained toxins that could result in adverse conditions such as severe watery diarrhoea, hepatic failure, hallucinations and hepatocarcinogen. Comfrey tea has been linked to liver disease, and lobelia tea can cause vomiting, breathing problems and convulsions.

As a guide for using herbal remedies, it is suggested that the following should be kept in mind.

* It should not be assumed that because something is natural it is safe.
* Plants are also sources of potent chemicals and can be highly toxic.
* Children should not be given herbs.
* Large quantities of any type of herb should not be taken.

Beware of exaggerated claims made on behalf of herbal preparations and do not trust your health to unqualified practitioners using titles such as, "herbalist", "herb doctor" and "herbologist".

Advice from heath food store employees should not be taken as qualified medical advice as few, if any have had medical training — they are there simply as salespersons.

Richard Hyatt, an advocate of Chinese herbal medicine, had this to say in his book, Healing with Chinese Herbs:

''The author wishes to impress upon the reader that this text is by no means to be considered a home medical adviser ... some of these herbs can be extremely toxic when used incorrectly. In certain cases Chinese herbs alone would not be sufficient to treat the illness and should be used in connection with acupuncture, diet, massage, and/or Western medicine. In such cases reliance on herbs alone could allow a disease to progress to a more serious stage".

A caution such as this from an advocate leads one to ask why use Chinese herbs in the first place?


Am Pharmacy. 1988. Many herb teas are toxic, NS28:230-1. April 1988.

Baron, R.L. and Vanscoy, G.J. 1993. Natural Products and the Athlete: Facts and Folklore. The Annals of Pharmacotherapy, Vol. 27. pp 607-615. April 1993.

Griggs, Barbara. 1987. Green Pharmacy, Robert Hale Ltd., Clerkenwell Green, London.

Huxtable. 1992. The Myth of Beneficent Nature: Risks of herbal preparations, Annals Intern Medicine Vol. 117, No.2, p.165-166. July 15, 1992.

Hyatt, Richard. 1984. Healing with Chinese Herbs, Healing Arts Press, Rochester, Vermont.

Larkin. 1983. Herbs are often more toxic than magical, FDA Consumer, October.

Le Strange, Richard. 1977. A History of Herbal Plants, Arco Publishing, New York.

Snider, Sharon. 1991. Herbal Teas and Toxicity. FDA Consumer, p. 31-33, May 1991.

Tyler, V. 1993. Herbs of Choice, Harworth.

[From: Edwards, H. 1999 Alternative, Complementary, Holistic & Spiritual Healing, Australian Skeptics Inc]