Number 24
January/February 2000

Herbs in this issue:



Sida cordifolia


A Note From Dr. Leung

    I see a rather disturbing trend happening in the field of alternative medicine which, I am sure, some of my colleagues have observed as well.  It is the continued publication of sloppy research data and manuscripts, along with the “marketing-precedes-quality” attitude of many manufacturers and marketers, confusing consumers with bogus and often worthless (but safe) products on the one hand, and potentially dangerous ones on the other. If unchecked, this trend may become mainstream in 5 years, which would then be too costly or impossible to reverse.  And herbs would go the way they had gone after the emergence of synthetic drugs, except that this time around, it would not be synthetic chemists who did them in, but “bad apples” within the herbal industry itself.  Instead of synthetic drugs, chemicals from herbs (which invariably will be synthesized) would replace the herbs.  These chemicals would become dietary supplements, nutraceuticals, phyto-nutrients, functional foods, food additives,


Dr. Leung is author of the Encyclopedia of Common Natural Ingredients Used in Food, Drugs, and Cosmetics (Wiley-Interscience), which was published in 1980 and revised in 1996. He is also creator of PHYTOMED, a prototype computer database on Chinese herbal medicine developed under contract with the National Cancer Institute.


OTC drugs, and/or prescription drugs.  The beneficial herbs would no longer be necessary, especially since scientific and lay publications by then would have generated so much misleading or useless information on “herbs” and “herbal products” due to imprecision relating to their identity,  it would be an easy excuse for the uninformed scientific and medical establishments to declare them “unscientific” and “worthless.” 

        Because of DSHEA, it is now so easy for anyone to introduce any chemical as a dietary supplement, as long as it is present in an herb, no matter how minor its concentration.  Then its suppliers or marketers can claim that this chemical “supplement,” unlike an herb or an herbal extract, will meet vigorous modern scientific criteria, because, according to them, we can now chemically control its quality and efficacy, meaning only the chemical’s concentration.  There are already numerous examples, including ephedrine, synephrine, caffeine, and huperzine A. 

        Ephedrine is a controlled drug that cannot be sold by itself as a dietary supplement, but it can be and is legally sold in dietary supplements.  If cocaine had not gotten so much bad press, it too may have been legal to be sold in the form of coca extracts.  After all, Coca Cola started with coca leaf extracts, although, for obvious reasons, the company may not want to be reminded of this despite the fact that cocaine has long since been removed from the coca extracts they now use in their secret formula.  Coca to the Andean Indians is like tea to the Chinese.  However, unlike the Chinese use of tea as a brew, the Andean Indians chew coca leaf with lime on a regular basis to give them the stamina necessary to survive in the high Andean altitudes.  It is a way of life with them for many centuries. Like tea and coffee, coca leaf has a long history of safe use as a supplement by millions of people over time.  And indeed, in its natural milieu, coca leaf is certainly safe as a dietary supplement, as evidenced by its continued use up to this day, particularly in Peru, Ecuador, and Bolivia.  On the other hand, although mahuang has been a safe drug for millions of Chinese over several millennia, it has never been used as a daily supplement, nor has its alkaloids been selectively extracted and used in a dietary supplement the way it is now being used in the United States.  Based on a historical context, even coca leaf has a broader “safe food use” history than mahuang, yet it is illegal to use coca leaf in North America, not to mention one of its main active components - the widely abused cocaine.  And cocaine to coca is like caffeine to coffee and guarana, or catechin to tea.  The chemicals don’t represent the botanicals in their traditional uses and properties.  Even if mahuang had been safely used in China as a daily “supplement” like tea or coca (which it has not been), its safety could only be claimed for the herb or its traditional extract (water decoction or infusion) and NOT for its ephedrine.  The latter, whose stimulant and “thermogenic” properties are being promoted, is what is actually being used.  The mahuang herb or its extract is only used as a carrier (or excuse) for the ephedrine.  Interestingly enough, whether by design to confuse the consumers or simply due to ignorance or negligence, Metabolife International on its Website quotes its medical director as follows:  Dr. Smith suggests that consumers should look for an ephedra product that lists the exact amount of ephedrine and caffeine per serving on the label.  The Physicians Desk Reference for Herbal Medicine states that ma huang is safe at doses up to 300 mg per day – more than three times the maximum recommended serving of Metabolife 356.  The fact is that mahuang or ephedra is NOT ephedrine, but it normally contains 1-2% of total alkaloids, 30-90% of which is ephedrine, the remaining alkaloids being pseudoephedrine (a safer drug, widely used as a decongestant), N-methylephedrine, N-methylpseudoephedrine, norephedrine, norpseudoephedrine, etc.  A dose of 100 mg of mahuang only contains 1-2 mg of total alkaloids (only part of which is ephedrine!), which is certainly not what is present in Metabolife’s product!

We Americans sometimes tend to take a good thing and abuse it.  Thus coca has turned into cocaine, and, to a lesser degree, coffee has become caffeine.  Although mahuang is not even in the same league as a traditional food, it is being used as a pawn for ephedrine, with companies promoting the safety of mahuang but the strong effects of ephedrine.  When are we going to place it in the proper category, such as OTC or prescription drugs?

Leung, A.Y., and S. Foster, Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics, Wiley-Interscience, New York, 1995, pp. 179-180, 227-229.


Shameless promotion – twisting of facts

When promoting products, certain marketers and “hired guns” (technical experts hired by marketers, especially of shoddy products, to lend credibility) frequently come up with incredible stories about herbs.  Here is one I came across on the Internet.  This relates to the ephedrine-containing herb Sida cordifolia.  I first came across this herb when I was a graduate student working on biogenic amines to which ephedrine belongs.  While looking up the sources of these amines, I noticed several Sida species listed in Willaman and Schubert’s book on plant alkaloids as containing ephedrine.1  Hence the presence of ephedrine in Sida species has been stuck in my mind because Ephedra species and Sida species are from completely different classes of plants, not just different species or genera.  The former is a gymnosperm while the latter an angiosperm.  This memory was reinforced about 10-12 years ago when I first learned about the presence of ginsenosides in Gynostemma pentaphyllum, which is from the gourd family, a completely different type of plant than the true ginsengs.  This is a second incidence of highly unique chemicals being present in very different kinds of plants.  The second time I came across Sida was maybe 5-7 years ago, when it started to appear in suppliers’ product lists.  I immediately made the connection of attempts by suppliers to introduce ephedrine into a product without evoking the name “ephedra” or mahuang, because at one point during that time, the status of mahuang in supplement products was rather shaky.  In any case, the point I want to make is that to many marketers it is not enough simply to introduce ephedrine into a product using a plant (any plant) as an excuse (carrier), they find it necessary to make up an untrue story to go with its marketing.  Thus when describing Sida cordifolia as an ingredient in its Weight Loss Formula on its website, the company, Viable Herbal Solutions, writes,

“Sida cordifolia has been used for over 2,000 years to treat bronchial asthma cold & flu, chills, lack of perspiration, headache, nasal congestion, aching joints and bones, cough & wheezing, and edema.  In Western terms, Sida cordifolia is considered to have diaphoretic, diuretic, central nervous system stimulating and anti-asthmatic activity.  The stem of this plant contains a number of active compounds, including small amounts of an essential oil, and most important, 1-2% alkaloids composed mainly of ephedrine and pseudoephedrine, with ephedrine ranging from 30-90%, depending on the source.  The effects of ephedra are generally attributed to the alkaloid “ephedrine” which produces central nervous system (CNS) stimulation, peripheral vasoconstriction, elevation of blood pressure, bronchodilation, cardiac stimulation, and a decrease of intestinal tone & motility, among other effects.  According to Dr. Albert Leung in his second edition of “Encyclopedia of Common Natural Ingredients Used in Food, Drugs, and Cosmetics” (John Wiley & Sons, 1995), the central stimulant action of ephedrine appears to be mediated by ‘1-adrenoceptors’, and not by ‘dopamine receptors’.  He also notes that pseudoephedrine has similar activities as ephedrine, except that its hypertensive and central nervous system effects are weaker.  Mark Blumenthal, editor of HerbalGram and executive director of the American Botanical Council, has stated that he has used the stems & twigs of this Chinese herb as a cold remedy for 20 years.  He points out that the effects of ephedrine, a stimulant alkaloid, should not be confused with those of the whole herb itself.  This is a good example of how the effects of a whole herb, and its isolated constituents, must be considered separately.  One should not confuse ephedrine and pseudoephedrine with ephedra, just like one shouldn’t confuse pure caffeine with coffee.”

It is obvious the marketers here are only interested in ephedrine and not the plant extract; nor for that matter the Sida or Ephedra plant.  Their quotes on ephedrine’s pharmacological effects are lifted almost word for word from the ephedra entry in my Encyclopedia.  There is nothing in this description of Sida cordifolia which applies to this plant.  Even its reference to Sida’s purported 2000 years of use was copied word for word from the description of mahuang in my book.  I have every reason to be critical of these people who twisted the facts and used my name to lend credibility to their product.  And this is not the first time my name has been directly or indirectly used without my consent in promoting products.  I discovered this particular promotional write-up during a continual effort to document a former client’s repeated unauthorized use of my name to market one of his products, even though this product is no longer the same and does not have my support.  All this is done in order to document this former client’s misappropriation of my name and likeness, in order to assess monetary damages in my legal proceedings against him and his company. 

        The fact about Sida cordifolia is this.  It belongs to the Malvaceae or marshmallow family.  It was a rather obscure herb in America until some “creative” supplier or formulator discovered that it contains a small amount of ephedrine.  Then suddenly it became a prominent herb to surreptitiously replace mahuang.  According to one of the major authoritative references compiled by colleagues of the Institute of Chinese Materia Medica, Academy of TCM, in Beijing,2 the whole plant is used in medicine.  It has febrifuge, detoxicant, and antiswelling properties; disperses contusions, facilitates menstruation, and aborts fetuses.  It is traditionally used in bronchitis, mastitis, sores and boils, and appendicitis.  It grows in southern China, including the provinces of Fujian, Guangxi, and Yunnan. That’s it!  This work lists only modern references, indicating there has been little or no historical documentation, probably not even in 100-year-old herbals.  I have not followed the literature of this herb, but my gut feeling is that it is simply used as a vehicle to carry ephedrine from other sources to pass this drug off as a legitimate “dietary supplement.”  The ad’s quote of Mark Blumenthal’s comment is untrue, or at best misleading, because, according to Mark, he only used the mahuang herb and not any Sida plant.  But it certainly is to the marketers’ benefit to keep things vague, so that consumers reading the promotional literature are led to believe that Sida cordifolia is a commonly used herb, described by me in my book and used by Mark Blumenthal!

(1) Willaman and Schubert. 1961. Alkaloid-Bearing Plants and Their Contained Alkaloids. U.S. Government Printing Office. Washington, D.C.;  (2) Inst. Ch. Materia Medica., Ch. Acad. Trad. Ch. Med., Eds. 1996. Quanguo Zhongcaoyao Mingjian. 3 Vols. People’s Health Publications. Beijing;  Leung, A.Y., and S. Foster, Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics, Wiley-Interscience, New York, 1995, pp. 227-229.


Astragalus to improve memory and intelligence?

        Astragalus root is one of my favorite tonic herbs.  I have written about it often in previous issues of this Newsletter.  It has a wide variety of traditional properties and modern pharmacological activities.  When traditionally used as a tonic, it imparts many of the benefits of Asian ginseng, but few of the latter’s adverse side effects (e.g., hypertension, agitation).  Its traditional extracts, if properly prepared and used, can deliver many of its well-known traditional benefits, such as healing (wounds, ulcers, etc.), promoting tissue regeneration, removing toxins, disease prevention (especially cold and flu), and strengthening body qi (vital energy), etc.  Biological activities discovered in astragalus root and its extracts include:  antioxidant, immunomodulating, antimutagenic, hypoglycemic, antiviral, liver protectant, cardiovascular (hypotensive, vasodilating, etc.), and many others.  These effects are not due to a single compound or a single class of compounds but rather, to different types of components, with saponins (triterpene glycosides), polysaccharides, and flavonoids playing a key role, due to their predominance.  Other compounds, such as choline, betaine, and amino acids, if selectively extracted, also play a role in the biological activities of astragalus. 

        The ability of an aqueous extract of astragalus root to improve memory and learning in mice is reported in an article published in the Chinese Journal of Traditional Chinese Drugs by researchers at the Guangxi Research Institute of Traditional Chinese Medicine and Chinese Drugs.3  The root used was identified as that of Astragalus membranaceus by Prof. Luo Jin-Yu of the Department of Chinese Materia Medica.  The extract was prepared by boiling the herb 3 times, 30 min each time.  The combined extracts were filtered and the filtrate evaporated to a syrupy consistency, which was then refrigerated.  Although the dosages of the extract used are reported as 35 g/kg and 50 g/kg, administered ig, there is no indication whether these amounts were based on the raw root or the actual weights of the water extract (of undefined strength).  But at least we know the researchers used a hot water extract, unlike many publications in reputable journals, which do not specify what were used in the reported studies [see Issue 18, pp. 1-2; HerbalGram 48, pp. 63-64].  Using the foot-pad-electrical-shock-avoidance method and after conditioning, 4 groups of mice (10 each) were subjected to the following treatments:  The control mice, Group A, were given 10 ml/kg distilled water; Group B were given either 10 ml/kg of 40% ethanol or 8 mg/kg of anisodine; Group C were given simultaneously 35 g/kg of the astragalus water extract (extractives) and one of the above drugs; and Group D, as in C, were given simultaneously 50 g/kg of the extract along with one of the drugs.  The mice were observed, during a 5-minute period, for the number of times they forgot to remain on the safety pad and leapt to the electrified pad.  Compared to the average number of mistakes (100%) made by Group B animals with drug-induced memory loss in both experiments, the astragalus extract reduced the error rate to 80% and 70%, respectively, in alcohol- and anisodine-treated animals (Group C).  A higher dose of astragalus extract (Group D) redued the error rate further to 40% in alcohol-treated animals and 50% in anisodine-treated animals.  In comparison, the control mice (Group A) had an error rate of 20% in both experiments. 

        Although this report is flawed, especially in the ambiguity of the amounts of extract administered and the fact that the experiments were only performed once, I find the results rather interesting.  If the authors had used the dosage of 50 g/kg to mean 50 g of “extractives from the root”/kg, then, when extrapolated to a person of 60 kg (132 lbs), he/she would have to ingest a concentrated water extract of 3 kg (6.6 lbs) of astragalus, which, depending on the concentration, can be up to 4 l (4 qt) of liquid!  This would be equivalent to drinking a gallon of a syrupy brew!  Although bulky, it probably may not be deadly, because the authors also report no fatalities in an acute toxicity test using twice the amount.  Thus, after mice were administered ig 100 g/kg of the same extract daily for 7 days (accumulative dose, 700 g/kg) and observed for 12 more days, no fatality was observed.  There were also no obvious toxic side effects, with the exception the mice were rather calm within an hour after administering the extract!  Poor mice!  After ingesting even a gallon of that stuff (not to speak of 2 gallons), I would be stuffed and calm too!

(3) G.X. Hong et al., “Studies on Memory-improving Effects of an Aqueous Extract of Astragalus membranaceus (Fisch.) Bge.,” Zhongguo Zhongyao Zazhi, 19(11): 687-688 (1994);  Leung, A.Y., and S. Foster, Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics, Wiley-Interscience, New York, 1995, pp. 50-53.


More Books on Herbs?!

        Just 10 years ago, there were few books on herbs.  Among them, only a small handful quoted scientific data.  But now, there are literally hundreds of such books, most of which invoking scientific or clinical research data.  How many of these do not contain information (or contain minimal information) that is misleading?  Probably only a very small handful.  And they may not necessarily be the best sellers or the most well promoted ones either. 

In traditional herb books in which no scientific data are invoked, whenever the name of an herb is used, it is understood to be the herb used in its traditional context, such as in the form of the herb powder, tea, infusion, or decoction.  Each one of these forms contains basically the same type of components from the herb, though in different concentrations.  One would not think of the “herb” as being an extract containing high concentrations of a specific chemical fraction (e.g., flavonoids, triterpenes, sterols, etc.) which may have very different pharmacological effects than those of the herb.  But in a few recently published major herb books which I have gleaned, the authors don’t clarify whether the “herb” they are describing is the herb in the traditional sense or a hitherto unknown chemical entity, such as an acetone extract, alcohol extract, polysaccharides, flavonoids, catechins, triterpenes, coumarins, etc.  Whether due to negligence or ignorance, they essentially have equated component(s) of an herb to the herb itself.  And they don’t distinguish related herbs either.  For example, in a recently published, well-promoted best-seller, used by medical professionals, American ginseng is not differentiated from Asian ginseng, nor is there consistent and clear distinction among herbs and their extracts.  Also, in another herb manual, whose hawthorn entry I have had a chance to review, the authors talk about hawthorn as if it were a well-defined single-component drug, which a consumer can buy from a health food store for treating his heart condition, as long as it is “standardized.”  But does powdered hawthorn or hawthorn tea actually have these types of clinically “proven” cardiovascular effects or does only a certain specific extract of hawthorn have these properties?  Without this more precise information, we are not doing the public a service.  Instead, we are contributing to the continued accumulation and dissemination of misinformation.  As highly trained professionals, we have an obligation to provide the public with clear and accurate information on herbs and herb research.  The most important and, at the same time, the most neglected area of herb research and reporting is product definition.4  Without clearly defining what we are researching on or talking about, the resulting data or publication will be a waste of our time, effort, and money.  So, let’s try our best to define exactly what we are reporting [Issue 18, pp. 1-2; Issue 19, pp 2-3].

(4) Tyler, V.E., “Product Definition Deficiencies in Clinical Studies of Herbal Medicines,” in press.