Major Herbs of Ayurveda, edited by Elizabeth M. Williamson. Compiled by the Dabur Research Foundation and Dabur Ayurvet Limited. Churchill Livingstone. London. 2002. 361 pp., hardcover with color photographs, index, glossary, therapeutic guide. $49.95 ISBN 0-443-07203-5
There is a paucity of books on Ayurvedic herbs in English, so that all new contributions are of special interest. The last significant effort along these lines was the CRC Handbook of Ayurvedic Medicinal Plants, by L.D. Kapoor (CRC Press, 1989). Unfortunately, the 400-page text cost $400 and did not find its way into many libraries as a result; a few years later, a lower cost reprint under the name Handbook of Ayurvedic Medicinal Plants: Herbal Reference Library (CRC Press, 2000) came out with a price of $150, which made it somewhat more available. That text includes monographs on 251 plants, giving different names, their habitat, distribution, chemical constituents, pharmacology, therapeutic uses, and dosage.
Like this prior book, Major Herbs of Ayurveda is a collection of monographs with essentially the same categories of information, focused in on fewer herbs: there are 70 monographs. The new text, which becomes affordable to many more potential readers (at $50) and is 13 years newer than Kapoor’s, should be judged on the basis of its utility for people who wish to study and, perhaps, make use of Ayurvedic herbs.
Major Ayurvedic Herbs, like other herb books comprised of monographs reviewing herbal research, presents as many reports as possible, and does not provide commentary on the individual research reports. Thus, old research (from 40 years ago) and new research (from last year) are treated as equal; well-controlled carefully designed studies and poorly controlled weak studies are also treated with equality. The only advantage of this approach is that when seeking background information on an herb, virtually everything that has been done is there for handy access; the disadvantage is that most readers cannot get any sense of the significance (or lack thereof) of various statements.
A challenge in producing any such book is accurately presenting a brief summary of what is found in the usual 15—30 (or more) references used to write the monographs; each monograph includes about two pages of text (not including the reference list). To illustrate the situation, I have selected an herb monograph that I think is typical: cyperus or nut grass (Cyperus rotundus L., Cyperaceae), which is called mustak in Sanskrit, and will discuss the main sections involving research and the problems that are encountered.
Well-studied herbs will often be subject to several investigations revealing chemical constituents. Such studies are not always aimed at determining the identity and quantity of major active constituents, but, rather, at finding novel chemical compounds that might eventually be found to have unique properties. Some of these compounds may be present in trace amounts. As a result of these efforts, one will end up with a long list of isolated chemical constituents, but little idea of what contribution, if any, they make to the traditional or modern uses of the herb. In the case of C. rotundus, a 1967 report is cited which states the essential oil of the rhizome constitutes about 0.5-0.9 percent of the material, and is comprised of broad groups of aromatic chemicals (e.g., sesquiterpenes, epoxides, ketones, monoterpenes, and aliphatic alcohols). Then, based on a study published in 2000, a listing of about 20 specific chemical compounds is provided. It would have been helpful to know if any of these constituents had been suggested to be an active compound explaining traditional or modern uses, yet such commentary does not appear. The study from 2000, though it may list trace ingredients, was obviously not even available for inclusion in Kapoor’s text.
The review of pharmacology experiments for C. rotundus presented in Major Ayurvedic Herbs indicates that it is anti-emetic, anti-inflammatory, antipyretic, anti-malarial, anti-obesity, anti-bacterial, cytoprotective, estrogenic, tranquilizing, hypotensive, muscle relaxing, and has an effect on pigmentation. This is a comprehensive report of what has appeared in the literature, but it can be misinterpreted easily. Thinking in terms of hot-button subjects today, estrogenic activity of an herb is one area of interest (an aspect deemed desirable or to be avoided, depending on the individual), but the report is from 1956, with only this statement appearing in the book: "the essential oil exhibited mild estrogenic activity." With only mild activity, and less than 1 percent content of essential oil, and no follow-up reports in nearly 50 years, one suspects that the estrogenic activity is a non-issue. Another area of interest is weight loss: this report comes from a 1992 randomized double-blind placebo controlled pilot study (which could not have appeared in Kapoor’s 1990 book). It was claimed, in the brief presentation, that 30 patients receiving the powdered herb experienced weight loss, along with a drop in cholesterol and trigylcerides (no specification of herb dosage, or amount of change detected). Apparently, there were no follow-up studies – I checked PubMed to make sure the author hadn’t missed something – suggesting that the effect was minor and not worth pursuing during the past decade; the book didn’t mention whether the effects observed were statistically significant. One wonders if the pharmacology studies and clinical applications described here have anything to do with traditional Ayurveda, as opposed to just screening by modern research techniques for various potential new uses.
Under dosage, the specification in Major Ayurvedic Herbs is, "Powder: 1-3 grams; Decoction 56—112 mls." One is left uncertain as to whether these doses were the same as those used in clinical studies (such as the above-mentioned obesity study), whether these are one-time doses or cumulative daily doses, and what amounts of herb and water are used to make up 56 ml of decoction. At the beginning of the book, I don’t find an explanation. Under preparation of medicines, for decoction it only states: "The herb is boiled in water and the volume reduced."
In sum, compared to other monographs on Ayurvedic medicine, this book is updated to include considerable amounts of new information. The reader should be aware that there are problems with this monograph approach, problems similarly found in other books of herb monographs, of listing information without filtering, commenting, or elaborating sufficiently.
As a result, practical use of the information is quite difficult. This deficiency is unfortunate, as the author, a senior lecturer in pharmacognosy and phytotherapy at the School of Pharmacy, University of London, has the background and insight to add some professional commentaries that would enlighten the reader.
Despite the drawbacks mentioned above, I’m very pleased to add this book to my library of texts on herbs and traditional medicine, including Ayurvedic herbs. It helps define which herbs have been subjected to considerable research and what research has been undertaken to date (in very brief outline form) in terms of chemistry, pharmacology, and clinical studies. I do not find the relatively small number of herbs presented in the book as a deficiency, because this work is not an effort to be comprehensive in terms of plants used in the tradition. A feature I like having in this book is the listing of Ayurvedic properties in English, usually not translated in other books. Hence, for C. rotundus, the herb is classified as bitter and astringent, light and dry, cold, pungent, and having the properties of pacifying kapha and pitta (very roughly, phlegm and fire). Also, the short paragraph introducing each herb in Major Ayurvedic Herbs often has useful information about its dominant use in Ayurvedic practice, the origin of its name, and any problems with confusing other species with the intended one. When such information is offered (it is not in the case of C. rotundus, however), I find it a useful summary as is the paragraph on traditional and modern use.
– Subhuti Dharmananda, Ph.D. Director, Institute for Traditional Medicine Portland, Oregon