Dr. Michael Tierra L.AC., O.M.D.

A shortened and more carefully edited form of this article is published in two parts in the February and March, 1999 issue of Natural Foods Merchandiser. This is an earlier more unedited version with a lot more facts and information that could not be published for the sake of space. If you are interested in either piece for publication in other magazines or other sources contact mtierra@planetherbs.com

Why Standardized Herbal Extracts?

An Herbalist’s Perspective

Michael Tierra, L.AC. O.M.D., Founding Member of the American Herbalist Guild

For many, herbal medicine represents our interdependent connection with nature. This exerts both direct and indirect effects on us in many ways, not least of which is an affirmation of our relationship with plants. Unfortunately, this is becoming all too frequently overlooked in an effort to capitalize on what, according to New Hope communications, the latest total herb sales was at 4 1/2 billion dollars for 1997. A significant part of the increase of sales is based not merely on the sale of popular herbs such as St John’s Wort , Ginkgo, Echinacea, Garlic and Saw Palmetto, but specifically their use in the form of standardized extracts.

Standardized extracts arose out of the need to create a uniform product for clinical trials. Broadly speaking, there are two types. One is based on identifying and quantifying an extract to a characteristic chemical marker compound. The second, identifies and concentrates one or more as active constituents, making it closer to the level of a chemical isolate. This means that other naturally occurring constituents are displaced at the expense of one or a number of compounds.

Those who support standardized extracts believe that they represent a trend towards higher technological refinement. They believe that they will provide a more consistent, stronger and more effective product backed by chemical analysis to confirm the presence and ratio quantity of one or a number of characteristic plant constituents. They further assert that this will increase consumer confidence and that this is ultimately good for greater acceptance of herbs by the medical establishment and the mainstream.

Certainly many of these are positive in many of these respects but there remain important critical issues to consider. Quality and effectiveness may be compromised in a number of ways:

  1. For the extracts based on active constituents, the high degree of concentration causes a corresponding displacement and lack of other constituents, which in a few cases have been subsequently shown to be even more effective than the originally presumed active constituent.
  2. Again for active constituent extracts, given that there may be only a partial representation of the herb’s normally occurring constituents, this limits the broad range of traditionally known properties and uses of an herb in favor of a single use.
  3. The use of chemical constituents as active or marker compounds creates misinformation encouraging the misuse of herbs as a substitute for drugs. This demeans in popular understanding the broader context of their use for the treatment of underlying imbalances as the cause of disease.
  4. Not all herbs branded as standardized are manufactured the same. Some involve methods that are not dissimilar to a more highly refined tincture or a concentrated dried extract while others employ the use of toxic solvents that may go against the sensibilities and ethics of individuals who are attracted to the use herbal remedies as an alternative to drugs. Furthermore, different methods of standardization produce significant differences in the finished product of which the consumer is not aware.
  5. The need to extract high isolates of a single biochemical constituent fosters poor harvesting and wildcrafting (ecologically sound harvesting of wild herbs) where quantity is sacrificed for quality.
  6. The relationship of plant to human is challenged so that people are less likely to appreciate the fact that an herb growing amongst the weeds in their garden may make as effective or an even more effective remedy than a standardized extract.
  7. Finally, since standardized extracts essentially represent a different form, it is not to be assumed that they will have the same effects as more conventional herbal products such as a non-chemically standardized tincture.
  8. The promotion of standardized extracts for the treatment of a named pathology, encourages marketing opportunism. This tends to distract from other herbs and products such as the use of Chinese Red sage (Salvia Milthiorrhiza) or Tienchi ginseng (Panax pseudoginseng) instead of hawthorn for heart disease, chrysanthemum flowers (Chrysanthemum morifolium) instead of feverfew for migraine headaches and honeysuckle blossoms (Lonicera javonica) instead of echinacea for the common cold.
  9. The technology necessary to produce truly standardized extracts as espoused by some of their leading exponents greatly changes the way herbs are handled at all stages from growth to final product. Some proposed trends such as the exclusive use of cultivated herbs over wild harvested ones, is counter to the traditional time-honored principles and practices of herbal medicine. Herbalists have always felt that herbs grown in the wild are superior to those under cultivation and by definition, wild herbs cannot be standardized. To manipulate herbs to conform to an artificial process of standardization makes them more like ‘˜phytopharmaceutical’ drugs. This in turn means that they can only be manufactured into products by well-vested pharmaceutical companies to be distributed and sold in pharmacies under prescription by medical doctors. Herbal medicine is a rigorous study and medical practice unto itself. It is presumptuous to assume that the majority of medical doctors are or ever will be qualified in their proper use. With profit as the primary motive, there is good reason to distrust pharmaceutical companies considering that it was from this sector that one may largely attribute the nearly complete suppression of herbal medicine from the mid-1920’s to the late 60’s. Up to recently, pharmaceutical companies were unable to cash in on the sale of herbs because they were unpatentable. With the advent of standardization, there is a pattern established where a company that is able to spend huge amounts of money on research is entitled to develop an exclusive patent for the process of extraction and standardization of an herbal product accompanied with a license to sell them on the international market.

History Repeats Itself

Is history repeating itself? The oft-repeated pattern of suppression followed by assimilation and relegated obsolescence of herbal medicine has occurred repeatedly since the suppression of tribal medicine and herbalists by the early church.

More recently, in 1901, the AMA whose supremacy was threatened by the growing popularity of homeopathic and Eclectic herbal medicine, reversed its ongoing antipathy “by cordially inviting them all to become members as long as they were prepared to give up their formal allegiance to Babels and sects. And once inside the fold they could, of course, practice exactly as they pleased: ‘˜when so elected, they are no longer homeopaths or eclectics, but are promoted to be plain physicians like the other of us’.”.

From the 1920’s to 30’s herbal medicine went into decline as discoveries of various chemical drugs and antibiotics were discovered. As today, with the possibility of developing patents on research and standardization protocols for herbs, pharmaceutical companies from the late 20’s to the present grow powerful and fat from huge profits made from the manufacture of patentable drugs.

From the late 1920’s to the present, with the help of the FDA who “shared this disdainful view of herbs,” the use of herbs was rapidly dropped from the United States Pharmacopoeia. Their reemergence reoccurred in the late 1960’s as increasing numbers of people were experiencing side effects from the tendency to suppress symptoms with drugs. Furthermore, there was an entire generation of anti-war hippies who felt disaffected from the mainstream and became interested in herbal medicine as part of a movement towards independence and self sufficiency,

Today we find pharmaceutical companies rapidly entering the herbal market. They first had to see the possibilities of profit based on expanding markets and a patentable product. The potential market is huge and growing incrementally. The next step, however, was how to realize enough profit to justify a costly campaign of research to increase credibility. Herbs unlike chemical drugs, themselves are not patentable. However, a standardized product used for research is patentable.

An herbalist who was one of the first to examine and pass judgment on standardized extracts and highly concentrated herbal preparations was Dr. Alfred Vogel of Bioforce Company of Switzerland. In his laboratory at Roggwil, Switzerland, he concluded that tinctures of the whole plant were more effective than fluid extracts that were extra concentrated according to active principles. Vogel eloquent states:

The “other” factors that control the effects of the preparation are nowadays known as “information” and are of decisive importance in plant medicines to the reinforcement of the body’s own curative powers. Depending on the dose involved, this “information” makes a considerable contribution to the effects of plant medicines. This “information” is destroyed by the artificial concentration of the active substances.”

An overview of some of the main German companies that were among the first to produce standardized extracts may give us some intimation of the direction of the herbal movement in the United States.

Lichtwer-Pharma is in a suburb of Berlin. In 1981 they became established as a company to manufacture a small product range of herbs. These include garlic, valerian, St Johnswort, and hawthorn. The goal of the company has always been to make plant-based medicine that would be acceptable to conventional medical practice. To this aim, it has invested heavily in research and technology.

Focusing first on one of the world’s most commonly recognized medicinal herbs, garlic, they were able through research to establish garlic’s effectiveness against increased blood lipids. With heart disease in Germany and the US being the number one killer, they found that a high quality garlic product standardized to 1.3% alliin, 0.6% allicin release was effective enough to launch a worldwide campaign selling Kwai garlic. The venture was phenomenally successful worldwide, with the sale of Kwai garlic in 1992 at around 40 million dollars. Because of the huge money it spent in research while seeking a license for its garlic product, the company was able to aggressively market a prescription garlic product to doctors on the basis of its ability to strengthen the heart and counteract many of the conditions associated with aging.

The same formula for success occurred by targeting the most common mental illness, depression. Again, investing in a strictly controlled clinical trial they used a standardized extract of St John’s Wort known as the “sunshine herb” because it stimulates bio-photons that increase sun absorption. To any vested pharmaceutical company the opportunity to validate the efficacy of a product leading to approval by investing sums of money for research is the formula for phenomenal success. Launched on the market in 1994 as Jarsin 300 and marketed to doctors by 1996, standardized extract of St John’s Wort was outselling its rival, Prozac. Does this really mean that a high quality St John’s Wort product will not prove to be as much as and perhaps even more effective than its standardized counterpart. In the case of hypericum this could be the case. Especially since recently it has been found that the active constituent that standardized St John’s Wort has been standardized to, .3% hypericin, is inaccurate because it is really another of the 100’s of compounds in St John’s Wort that is the real active, hyperforin. Already, German pharmaceutical companies are gearing up to market St John’s Wort standardized to its content of hyperforin.

While St John’s Wort outstripped Kwai garlic in annual sales, both of these were completely dwarfed by the sale of Ginkgo Biloba standardized to 24% flavoglycosides by Schwabe pharmaceuticals. Gingko Biloba nuts are traditional in Chinese herbal medicine as a lung tonic for asthma but few if any Chinese know of the use of the leaves as a remedy against the ravages of ‘˜baby boomer’ senile dementia. There may be an ancient reference for this use in the annals of Chinese medicine but essentially, this product sprang on the market with no reference to previous empirical data. As such it could be heralded as a triumph by western pharmacy over empiricism or traditional use. This was further underscored by the fact that based on their research, the most effective standardized form required 50 parts of the slightly yellowed autumn harvested leaves to be reduced to one part with further extraction with highly toxic solvents to arrive to produce this product. Sales of this product is unprecedented if for no other reason than the fact that there are no synthetic drugs known to be effective for senile dementia.

The pattern repeats itself, first launching it simultaneously as a prescription drug in Germany and France, total sales worldwide in 1992 of Gingko standardized extract was 195 million dollars.

A perusal of the editorial and advisory boards of leading magazines on herbs and alternative healing presents a wall of PHD’s, MD’s with perhaps a smattering of naturopaths and rarely a token clinical herbalist. Most are not on these boards because of their clinical experience in the use of herbs but because of their academic standing. Many of these such as Varro Tyler scarcely less than a decade ago could barely be counted as a supporter of herbal medicine.

I have always considered it profoundly naïve to expect that most researchers and academics whose funding directly or indirectly comes from pharmaceutical companies can be trusted to represent herbal medicine as an art and science distinct from the reductionist thought processes of contemporary medical science. As such, I find that the public media and various herb journals attempt to achieve credibility by including these unqualified individuals posing as having practical hands-on clinical herbal experience is very misleading. Certainly one of the most misleading of all stances that is all to often advocated is the patently inaccurate statements that the use of standardized extracts are the only way to assure identity, quality and efficacy.

As briefly described, by definition, a standardized herbal extract involves predetermining one or a number of biochemical constituents as either active or as marker compounds. The result involves two very distinct types of extracts.


One: a marker extract: This type establishes that a specified amount of a marker compound is present in the finished product. It must be remembered that a marker does not represent the active constituents but is selected as a biochemical constituent characteristic of the plant. In many cases, if this process uniformly increases all plant constituents to an intended level. In general, the insoluble compounds, such as cellulose and fiber, are excluded. In some cases the concentrated extracts remain dried and powdered while in others they are mixed with a neutral material such as corn starch, and in still others, the extract is mixed with the fine granules of the whole herb. The most important distinction is that marker extracts are not based on the concentration of a proven active constituent, but are used for positive identification or to create a higher degree of uniform potency. As for the latter, it as yet remains to be proven whether this is consistent with the potency of the whole herb.

Considering the fact that all herbal preparations are to a degree an extract, a marker extract that equally regulates all constituents, retains more relationship to the traditional way herbalists use herbs. Another problem is the propensity to overly promote one use over many others that it may have. This tends to be based on a named pathology, such as feverfew for migraines, St John’s Wort for depression, devil’s claw for arthritis. Traditional herbal medicine uses herbs more functionally rather than for the treatment of specific pathology. Felter described the Eclectic tradition’s specific indications for hypericum as including a range of conditions from spinal injuries, concussions, chronic urinary disorders, to various pains associated with bruising, injuries and puncture wounds and finally as a sedative for hysteria which may in modern usage translate to its anti-depressive properties.

There are some differences as to how each herb is treated but in general the following is a list of some of the better known Marker Extracts.

Examples of Marker Extracts: Artichoke (2-5% cynarin), Chamomile (1.2% apigenin/0.5% essential oil), Devil’s claw (5%harpogosides), Echinacea (4%echinacosides), Ephedra (6-8%ephedrine/pseudoephedrine), Feverfew (2.6% parthenolides), ginseng (5-15% ginsenosides), Goldenseal (5% hydrastine), Horsechestnut (20% Aescin), Uva Ursi (20% Arbutin), Gotu Kola (10%asiaticosides), Green tea (20-50% polyphenols), Licorice (12% glycyrrhizin), St Johnswort (0.3-0.5% hypericin), Schisandra (2.6-4% schisandrins), Valerian (0.8-1% valerenic acid), Willow (8%salicin).


Second: an active constituent extract : This regulates a specific biochemical constituent to a level that may not be naturally found in the plant. Concentrating 95% curcuminoids, for instance, in a standardized turmeric extract creates a product that while derived from the crude herb, is not expected to be naturally found concentrated at that level. This leaves only 5% of the other turmeric constituents with which the curcumin is combined.

There are at least three specific and obvious problems with pumping up one constituent of a product at the expense of its other constituents:

  1. The active constituent may indeed be eventually found to be not primarily responsible for the therapeutic action of the herb, i.e. other constituents may be discovered to be more biologically active.
  2. Herbs such as turmeric, milk thistle seeds and saw palmetto have many properties and uses. One of the problems with the promotion and intended use of standardized extracts in this category is that they may limit an herb’s range of influence. How do we know that by excluding the complex of chemicals found in each of these herbs, they don’t lose their more varied and diverse traditional functions? In fact, I would probably not use a standardized curcumin extract to promote blood circulation or warm and stimulate digestion. While Traditional Chinese Medicine (TCM) classifies it as warm (stimulating metabolism), emphasizing its anti-inflammatory curcumin content would make it more cooling (lowering metabolism).
  3. There are questions about safety when concentrations of one or a number of biochemical agents are allowed to be sold as food supplements when in many cases it may really be more of a phytotherapeutic drug. One example is Ephedra sinica or Ma Huang (the Chinese name). As a whole plant it has been used for respiratory conditions, especially asthma. According to Dr. Andrew Weil, M.D., ephedra has been replaced in medical practice by “pure, synthetic ephedrine,” based on one of the plant’s active constituents. While patients taking pure synthetic ephedrine, experience side effects of “jitteriness, insomnia and a feeling of being drained of energy all day,” he points out that a tea made of the whole herb “gives similar relief from asthma, but with “none or little of ephedrine’s toxicity.”
  4. Given the sensitivity around a small number of adverse reactions to certain herbs in the recent past, it would not take many complaints that would probably go against the herb rather than only its standardized extract. Again, not all of these issues would apply to every herb in this category.

The problem of exclusively promoting an herb as a standardized extract overlooks the range of many of its other uses. For instance, Milk thistle seed extract is specifically sold as a liver protective agent while the Eclectics according to Felter and Lloyd as quoted in Ellingwood described a much wider use. These include a dull aching pain over the spleen that passes up to the left scapula associated with pronounced debility and despondency, splenic pain with or without enlargement. Further uses indicate that it was known to improve blood circulation especially in the pelvis making it particularly useful for dysmenorrhea, amenorrhea and irregular passive uterine hemorrhages.

Examples of Active Constituents Extracts are Gingko (24% flavoglycosides), Milk thistle (80%silymarin), Grape seed (95% polyphenols), turmeric (95% curcumin), Saw palmetto (90% free fatty acids), Green tea (60%catechins), Cascara sagrada (20-30% anthraquinones), Bilberry (25%anthocyanosides), Pygeum (12% phytosterols), Kava (30-40% kavalactones).

It is known that in fact, very few herbs in trade are reliably standardized to known active constituents as opposed to possibly inactive markers? Joerg Gruenwald is one of the editors for the German Commission E Monographs, a recently published book that is regarded as the highest recognized standard in the western world on medicinal herbs and plant products.

He states that: “only 5% of botanicals are standardized to the one and only known active constituent, but even this is changing day by day. Sennosides in senna are still regarded as the active constituent in senna but the kava lactones in kava or the ginsenosides in ginseng are questionable as to whether there are no other actives involved.” He further points out that a “maximum of only 10-15 botanicals have undergone well controlled clinical trials and it is doubtful whether all of them will hold up to FDA standards.”

This means that one who exclusively relies on using a standardized extract based on known active ingredients, except for a very few, might be just as well or even better served by using a quality non-analyzed herb product. Certainly it will be cheaper in cost and even the quality of herb used is likely to be superior because the manufacturer would be selecting herbs based more on quality than quantity. Despite these considerations, Joerg Gruenwald is of the opinion that standardized extracts are “in any case more valuable than non standardized extracts and more valuable to the consumer.” Implying that presently there are shortcomings in present standardization methods, he echoes the opinion of a few researchers that there are shortcomings in current standardization methods, and offers the opinion that “the best way to standardize would be a bio-chemical standardization on the majority of active constituents.”

Imagine telling a traditional Chinese herbalist that they should only use phytopharmaceuticals in the form of standardized extracts. Do you not agree that Chinese herbal medicine, an empirically based system that has demonstrated efficacy for 1000’s of years is probably the most powerful “system” of herbal medicine on the planet? They do not treat primarily by named diseases but conditions that give rise to disease. This is what traditional herbal medicine is best able to do. Certainly concentrated extracts of all ingredients of high quality botanicals can be used in this practice and I use them a great deal in my practice as 5 to 1 dried extracts. They are not as effective as the nasty tasting herbs but there is better long-term patient compliance. So we lose and gain something in the process.

Except for researching the action of a specific or a limited group of plant constituents, why do we need them? What Rudy and Bonati are pointing to is that to truly standardize, every variable concerning the growth, harvest and preparation of a plant must be controlled. From their perspective, it is disadvantageous to use wild herbs because they may not be up to standard. Herbalists have for centuries used highly effective methods of selecting and sorting herbs according to their quality. This is also standardization. At the same time, there is a strong tradition that wild herbs are generally superior to cultivated.

The opposite is advocated by the advocates of standardization. Further, to accomplish the standard of standardization that is advocated to arrive at a truly standardized extract, it would require such tremendous technology that not only will smaller companies be pushed out of the picture, but it will only leave the pharmaceutical companies who have the $$ ability to even approximate such standards. Again the recurring leitmotif, why?

This movement while attracting more consumers to herbs is really luring them to what I am afraid is the ultimate eclipse of herbal medicine as an alternative. With the pharmaceutical companies in control, they have taken patients interested in herbal medicine and convinced them to come closer to accepting a more drug-like form called a “phytopharmaceutical.” Now who is in charge?

Anything can happen at that point of evolution. All that needs to happen is for science to come up with a synthetic of something that has enough of the virtues of hypericum with perhaps none of the unproven risk of photosensitivity, to for doctors to persuade patients, under the advice of the pharmaceutical company, to use the ‘˜cleaner’ and more effective hypericum-like synthetic.

Drugs go into obsolescence all the time. Once herbs are regarded as phytopharmaceuticals it is a short stretch for them to be considered as just another drug.

It seems that what we gain from this treatment of herbs is too little and what we lose, the ability to treat patients by a distinct medical paradigm encompassed by the term wholistic or traditional herbal medicine.

Currently the .3% hypericin of St Johnswort has been found to be inactive as an anti-depressant compared to a new compound called “hyperforin.” Because of this the Germans are now revamping their products to standardize to hyperforin. Herbalist, Jonathan Treasure believes that this points out the essential “flaw in assuming that any single compound is the active.” Considering the broader uses and applications of St John’s Wort , it is “conceivable that hyperforin standardized products will be devoid of anti-inflammatory, anti-viral, vulnerary, analgesic and anti-neuralgic activity until some bright spark discovers the “active” for each of these actions.”

Australian herbalist, Kerry Bone compared a standardized extract of turmeric at 75 to 95% curcumin with the constituents found in the whole root. He discovered that there were dozens of other constituents in whole unadulterated turmeric that also possessed anti-inflammatory properties. Some of these may be as potent or even more potent than curcumin. By concentrating curcumin to an unnatural 75 to 95% standard, some of the flavonoids and volatile oils (the warming element) are lost. Thus it may be that Standardized turmeric extract with 95% curcumin is most effective as an anti-inflammatory but not so effective as a digestive and circulatory stimulant. Again, there is nothing wrong with having both choices available turmeric high in the anti-inflammatory curcumin for joint and gall bladder inflammations and the whole root that can also be used for blood circulation and digestion. The unanswered question based on lack of research is whether the whole herb is as effective for inflammation as the standardized extract. Herbalists may argue that it is so then why bother making a standardized extract based on the high concentration of curcumin? Again, the reason for the original development of the standardized extract of turmeric was not because it would be superior but because it is more appropriate for controlled study and research based on the high concentration of curcumin.

Plant chemistry is extremely complex representing a vast number of chemical compounds. The complexity of this issue raises serious concern of what might be gained or lost if we limit ourselves to a standard of exclusively using only standardized extracts. The following is a citation on turmeric from Jim Duke’s herbal database:

Turmeric ‘“ for arthritis:

Analgesic ‘“ Borneol, caffeic-acid, curcumin, p-cymene, eugenol

Antidermatitic: Guiacol

Antiedemic: borneol, caffeic-acid, caryophyllene, curcuminoids (Tetrahydrocurcumin>Curcumin>Triethylcurcumin), eugenol

Antiinflammatory: Azulene, bis-(4-hydroxycinnamoyl) ‘“methane; borneol, caffeic-acid, caryophyllene (IC50+100 uM), cinnamic-acid, curcumin; eugenol (11 uM), feruloyl-4-hydroxycinnamoylmethane; alpha-pinene, protocatechuic-acid, beta-sitosterol, vanillic-acid Inhibit Cyclooxygenase: Curcumin; galangin (5.% M)

Inhibit Lipoxygenase: Borneol, caffeic-acid (IC27+5 mM), cinnamic acid

Inhibit 12-Lipoxygenase: Curcumin

Inhibit Production of Tumor Necrosis Factor: Curcumin

From this we see that curcumin, as the standardized marker for turmeric are effective for the widest number of applications. Further, it is a compound that is certainly unique to the herb. There are a few conditions, such as the use of turmeric for skin conditions (antidermatic) and a lipoxygenase inhibitor where curcumin has no relevance. This means that a 95% curcumin standardized extract of turmeric cannot be relied upon to be effective for skin conditions (a known use for the herb in India). We notice the wide number of other compounds that are indicated for the rest of the conditions and again, in a standardized extract, with 95% curcumin, we’d better be right that this is the most active component of the herb.

The American Herbalists Guild (AHG) was founded in 1989 in Santa Cruz, California. The Guild was originally conceived among other reasons to “Develop a professional body that promotes and maintains excellence in herbalism, including individual and planetary health.” The AHG is primarily intended to represent clinical herbal medicine in North America. Its professional membership, whose members are admitted through a process of peer review, represents a considerable number of years of collective clinical experience that should not be overlooked in any honest inquiry or discussion about the efficacy and safety of herbs. Considering the level of representation in the media’s advisory boards and research projects, one hardly finds in many of them professional clinical herbalists among.

Concerning standardized extracts, generally, professional AHG member, Christopher Hobbs has stated in a feature article for the Vitamin Retailer (March, 1997), “while the scientific work around standardization has certainly given our industry more credibility, especially in the medical field and the mainstream — don’t equate standardization with efficacy and potency.” While insisting on using high quality herbal products, most clinical herbalists would agree that standardization, too often used as a marketing ploy, does not necessarily guarantee that it exists in all projects sold as a “standardized extract.”


Why Standardize Herbal Products?

The primary reason standardized herbal extracts exist is because they are considered necessary to achieve as much control in double blind studies as is possible. Researchers, however, never intended to establish that standardized extracts were superior to whole herbs or more conventional preparations.

According to herbalist, Bob Brucea, “Standardization does have advantages. It produces a consistently strong product with guaranteed constituents. When you consider the quality of most commercial herbs, this at least assures that they have something in it and that the correct herb is being used.” He and many herbalists such as Canadian AHG herbalist, Terry Willard look to the brighter side with standardized herbal products enabling a quantum acceptance by more people including doctors and pharmacists who are accustomed to consistency and percentages of active constituents. As pioneer herbalist, Ed Smith satirically said, we need to accept the fact that “we baked the pie and now everyone wants to have a piece.”

The major proponents of standardized extracts view herbs as medicine in a way that is fundamentally different from herbalists.

Dr. Rudolf Bauer, one of the leading botanical research scientists in Germany states the three primary reasons for the standardization of herbs into phytopharmaceutical drugs. He states that 1. “If phytopharmaceuticals want to be regarded as rational drugs, they need to be standardized and pharmaceutical quality must be approved, 2. Also, in pharmacological, toxicological and clinical studies with herbal drugs, their composition needs to be well documented in order to obtain reproducible results, 3, The World Health Organization (Who) has recognized this problem and has published guidelines to ensure reliability and repeatability of research on herbal medicines, 4. This concept should be followed not only in research, but also in the production and therapeutic application of phytopharmaceuticals.”

The key here is the implication inherent in the word “drug” and the inclusion of herbs, which as “phytopharmaceuticals” are no longer herbs in the sense that a traditional herbalist might approach them but plants treated and rendered as close to the definition of a drug as possible. From the perspective of this paper, the question is what is involved in making a traditional medicinal herb conform to the standards of a drug i.e. phytopharmaceutical?

Herbs are described and identified as “chemovarieties” and “chemocultavars” that offer uniquely fascinating problems by the fact that they “are always mixtures of many constituents and it is much more difficult to characterize such a complex mixture than a pure compound.” Conceding that the “active principle (s) of compound are not always known,”

Who is it that needs herbs in this form and used in this way? Researchers attempting to get a grant or funding for research on the medicinal properties of plants, the pharmaceutical industry and the medical establishment, which is not interested in being transformed by wholistic herbal medicine but into changing it into something that will be acceptable within their paradigm, and the herb industry who through marketing, can capitalize on the union of science and herbal medicine to develop a competitive edge in the market. It is understandable that this would not sit well with most clinical herbalists and the many who were drawn to the use of herbs based on a need to affirm their connection and interdependence with nature.

The question really is whether this is necessary and to whom and for what? Is it necessary for effective herbal practice? Hardly — imagine telling a Chinese herbalist that it is best for he or she to use only chemically standardized herbal extracts in the form of phytopharmaceuticals?

It is a key point of this of this article, however, that standardized extracts, and I think we are mostly referring to active constituent extracts, have very specific applications as compared with commercial, non-analyzed whole herb products. As such they might not always be the best choice. Studies comparing the effects of standardized biochemical extracts with whole herbs or conventional preparations would be very enlightening. Unfortunately, so far there has been no enthusiasm for such a study because there is more profit to be made from the sale of standardized extracts.

Another reason favoring the use of standard extracts is that they assure positive identification that the herb is what it is claimed to be. Cheating and misrepresentation has been endemic in the field of herbalism at least since the time of the Egyptians and Greeks. We read in ancient records complaints of receiving bogus herbs or herbs of inferior quality. Michael McGuffin, co-founder of Zand Herbal Formulas and former chairman of the board of trustees of the American Herbal Products Association (AHPA) is one who sees standardization as a positive evolution in the use of herbs. He seems to agree with Michael Murray and Varro Tyler when he states that “a standardized extract can ensure that sufficient amounts of the herb’s constituents are present to deliver an efficacious product.” In fact, however, this is not quite accurate. What it does assure is that there is a sufficient amount of the “marker” compound.

While using standardized extracts based on a biochemical “marker” offer a high level of reliability in terms of knowing that one has the right herb, chemical deception has also occurred. Herbal extracts can and have, according to Jim Duke, been “spiked” to deceptively register a particular level of an individual marker compound in an adulterated extract using the wrong herb. Therefore, while a standardized extract of a particular herb may offer a degree of assurance that the product is what it claims to be, even with this method, it is possible to be deceived and cheated, winding up with the wrong herb in an adulterated form of a standardized extract.

Herbalist-acupuncturist David Maloney a licensed acupuncturist, Chinese herbalist and professional AHG member expresses concern that “when pharmaceutical companies start to use standardized extracts, we may perhaps see less scrupulous standards with the adulteration of artificially derived non-herbal compounds, say with coal tars, in order to increase profitability. This would comprise the additional compounds that are supposed to be with the “marker” and perhaps there may be no actual active constituents in the final product.” He facetiously asks the question, “how many “markers” do we need in each herb to authenticate the product?”

One consideration is that standardizing to a single biochemical compound requires exponentially higher quantities of herbs. Unless we are confident in the overriding importance of an isolated chemical constituent, as opposed to the use the whole herb, it is wasteful to support the harvest of tons of herbs for this purpose. Furthermore, the harvest of such huge quantities of an herb invariably threatens quality. We certainly don’t need to include as a description of standardized herbal products ‘˜standards’ that herbalists consider important such as ‘˜organic’ and ‘˜wildcrafted.’

Part of the implied assumption is that before the availability of standardized herbal extracts most herbal products were inferior. The truth is that there are many herbal companies who make high-quality herbal products. Further, one advantage a smaller company has over a larger one is that it needs less quantity to achieve superior quality, while the manufacturer of standardized products is more likely to sacrifice quality of botanical material for quantity. Whether using conventional herbal products or standardized extracts the primary guarantee is not in the form of the final product but developing confidence in the manufacturer.

Attempts at standardization of herbal products as previously stated, is not new. In fact it reaches far back perhaps to the first time someone threw some leaves into a cup of boiling water on a campfire to treat their upper respiratory condition, their digestion or their arthritis. Herbalists have defined standards of how and when to harvest medicinal herbs as well as how they may be dried, powdered and extracted in water or alcohol. All of these are processes of standardization.

Historically there have been highly sophisticated methods of herbal extraction and processing. They abound in folkloric, Traditional Western, Traditional Chinese Medicine (TCM) and East Indian Ayurvedic medicine. Some of these methods such as the detoxification of aconite by preparing it with salt and/or long boiling decoction are a mainstay of TCM practice. East Indian Ayurvedic medicine employed many ingenuous and complex methods of extracting, concentrating and preparing herbs for specific conditions. In this regard, the purified guggul sterones are traditionally extracted from crude guggul resin (commiphora mukul) in a botanical decoction consisting of equal parts chebulic myrobalan, emblic myrobalan and beleric myrobalan, a formula widely known in India as Triphala

While many believe that herbal medicine is generally safer for most conditions false assumptions are often made when this is based on the fact that it is because it is more natural. A natural poison can kill often as efficiently as a synthetic one. Traditionally, before the advent of modern synthetic drugs, the goal of healing was not predicated on whether it was a natural or unnatural method but only on whether it provided relief from suffering and disease.

What a standardized herbal extract purports to offer when it is standardized based on an active constituent, is the opportunity to use herbs in a more special way for specific predetermined therapeutic objectives. Ginkgo leaf standardized to 24% flavoglycosides to increase blood circulation, especially to the brain, is used instead of its more traditional use by the Chinese as a tonic for the lungs. Ginkgo is a special manufactured product using highly extracted leaf concentrate that has no precedent in traditional herbal practice. This is not inherently negative in any way. However, herbalists generally maintain that it is the interaction of the myriad’s of biochemical constituents that is responsible for their action. Other concentrated extracts based on a presumed active constituent such as ginseng standardized with 5 to 15% ginsenosides, turmeric with 85% curcumin and kava with 40 to 40% kavalactones, the valepotriates of valerian, the hypericin of St John’s Wort , are disputed even by researchers. In fact, they probably offer no advantage in terms of efficacy over the use of move conventional high quality herbal products. The fact remains that unless such distinctions are made, the exclusive recommendation for the use of standardized extracts is misleading.

All of these issues are contested today by herbalists and researchers throughout the world. One solution is to use of a Full Spectrum extract that combines the appropriate dose of active constituent extract mixed with the powder of the whole herb. Until these issues are resolved, this may be a way to receive the best of both alternatives.

How herbs are standardized

In fact, many of the processes of standardization are not standardized. Many herbs sold as standardized extracts are not consistently standardized to one marker. Nettle root is standardized by one company to 5% amino acids, by another to 8% sterols, and a third uses 35ppm, scopoline. Because it is not certain which of its constituents are responsible for its therapeutic action, Echinacea can be standardized to at least three different constituents and each used as markers by different companies. These include echinocosides, polysacharides and polybutylides. In fact, given this inconsistency, one might be as well or better off (certainly in terms of price) purchasing a high quality herbal tincture.

AHG. herbalist and owner and founder of Herb Pharm, Ed Smith, mentioned how of the 100’s of Kava products standardized with 30% kavalactones, there is disagreement as to what number of lactones to make the standard as well as the best ratio they should be presented. He further states that in order to make such high extractions of specific chemical constituents, it is impossible to harvest herbs at their optimum. It takes considerably more time and effort to harvest most herbs at their optimum stage in the quantities needed for extraction. The old US Pharmacopoeias specified the use of fully ripened saw palmetto berries. These are deeply blackish and purplish in color. Herbalists have witnessed migrant workers harvesting hundreds of tons of green, sometimes yellow or orange berries, which are then shipped to Europe to be made into standardized extract.

Ed posits that “the fact that such poor quality material is being used to make standardized saw palmetto is probably why the standardized form has to be used in much larger doses than the fluid extract from fully-ripened berries.”

Does standardization actually favor the use of inferior botanicals? All herbal traditions regard wild as opposed to cultivated herbs as superior. This is because the wild herb possesses adaptive qualities based on subtle factors of biochemical composition and potency that would be lacking in the cultivated variety. Without investigating or disproving this time honored understanding, the thought process that favors standardization reverses this in an attempt to control what A. Bonati describes as the “inconstant” nature of vegetable drugs, “influenced by several factors, “age and origin, harvesting period, method of drying and so on. ” From another perspective, in our determination to create biochemically standardized herbal drugs, representing “a body of information and controls that are necessary to guarantee constancy of composition — hence the standardized quality — of a phytopharmaceutical drug.” One thing that this suggests is that it would be preferable to use what herbalists consider inferior herbs that are cultivated rather than superior wild herbs for the manufacture of standardized extracts. In fact, of course, it makes no difference so long as certain constituents are present as either actives or marker compounds.

Another founding member of the American Herbalists Guild David Winston, an East Coast herbalist with over 25 years professional experience, points out that there is no standard for how standardized extracts are manufactured. This raises the basic question as to what is the best extract? Since industry has no standard even as to what chemical to standardize to or even what chemical methods to use to make standardized extracts there may be a significant non-standardized variance in the finished product. Again, considering the increased cost of standardized herbal products, this raises the question in many instances of ‘˜why bother?’

As stated, Adjusted biochemical constituent extracts involve bringing the product close to a total isolate. According to a number of sources including herbalist and herbal manufacturer Bob Brucea, co-founder of the American Herb Association this typically involves the use of a highly toxic and strong solvent such as hexane, benzene, methyl-chloride, acetone, etc. with an affinity for the intended constituent. It is impossible to completely evaporate and eliminate all traces of these solvents so there will be an FDA approved residue in the finished product. Of more serious concern is the adverse environmental impact with the possibility of these eventually draining into the ground water supply. For many, these are grave concerns and in the absence of research comparing the efficacy of adjusted biochemical constituent extracts with whole herbs or conventional preparations they may not see a compelling need to use extracts that are manufactured with these highly toxic solvents.

Further Considerations

It should not be news that the health industry including the herbal industry is driven by fads. It’s not always clear how or where many of these originate. With literally thousands of known medicinal herbs, everyone would like to find the magic bullet for a given condition. Rather than clamoring for a limited number of herbs as a standardized extract for treating a plethora of diseases, we should be more concerned about selecting the most effective herb or herbal formula. Neither quality nor potency can compensate for the fact that an herb may be ineffective for a given condition.

One of the fears from the increasing promotion of herbal standardized extracts is that it may make it difficult for small manufacturers of quality products to remain in business. This would not be an issue if, as we have mentioned, a standardized product has been proven to be superior to that of a traditionally made product. Small herbal companies may make from one to five gallons of tincture at a time. Considering that the manufacture of standardized herbal extracts may be wasteful and encourage the harvest of inferior herbs and that the cost for a biochemical laboratory assay ranges from $100 to $450 per test, it is not profitable for a small company to standardize on such a small scale.

As AHG herbalist, Chanchal Cabrera states, “Technology applied to botanical agents increases prices dramatically”— and this tends to make standardization more motivated by a “desire to make money than a desire to heal people or to understand herbal medicine.”

Standardized extracts arose out of the need to create a uniform product for controlled double blind, crossover, placebo-controlled clinical trials. Based on this, it seems reasonable to assume that to achieve a similar level of response, one should have access to the standardized version that was used in the study. That is why the public keeps insisting on the use of St John’s Wort with .3% hypericin even though hypericin is no longer considered the primary active constituent. What is missing from this equation is the fact that the basis for why the herb was selected was because of some prior level of traditional usage. With no proof that a standardized extract is superior in its effects to a quality traditional herbal product, there really is no reason to exclusively use the standardized version unless it is based on a high concentration of known active constituents. Even if this were the case as with the use of Ginkgo biloba leaf extract with 24% flavoglycosides, the use of the concentrated extract makes it uniquely indicated in a way that is quite different certainly in potency and the presence of tannins, from the properties of the whole leaf.

Chanchal Cabrera echoes the concern of many professional herbalists when she states, “The public is led to believe that these standardized products are somehow better than nature can make them and are more desirable than the simple plant remedy.” Later she pointedly asks, “Who really benefits by this technological approach to herbs? Are any of the standardized products really all that much better than traditional remedies? Are we in danger of losing our “roots,” of losing touch the earth-centeredness of traditional medicines?”

These sentiments are reiterated even more bluntly by Anita Hales an Alaskan herbalist, “I think politics and marketing are the main driving factors of standardization. Standardization is becoming a marketing buzzword to sell products that may not necessarily be better than another product. It’s a typical move to mediocrity not necessarily improvement.”

Martha Benedict, a California State acupuncturist and clinical herbalist with over 25 years of experience and a professional AHG member makes the point: Standardization of itself is a chimera. There are too many plant components, interactions and interdependencies for us to be so witless as to think we can CONTROL the outcome of a complex event merely by controlling one or a limited number of active components of a plant. What hubris! Are we about to recapitulate the same narrow thinking which makes Western medical drugs so dangerous?”

It is possible to guarantee optimum levels of all plant ingredients without laboratory analysis. An example of traditional methods used by herbalists for centuries were described in the St John’s Wort monograph by Christopher Hobbs, published in Herbalgram No. 40. Attention was directed to understanding all levels of growing requirements, best stage for harvest even to the best time of day that was optimum for yielding the highest levels of all known “active” constituents (evening). Other factors such as proper drying and storage were also evaluated. Though it requires training and experience this is a part of the art and science of herbal medicine.

When it is necessary to establish the positive identification of a plant, high-pressure liquid chromatography (HPLC) and nuclear magnetic resonance is used. These readings establish a fingerprint of the chemicals contained in the plant or extract. To establish the identity of a plant, matching biochemical fingerprints are all that is needed. However, it is possible to use the same process to only establish the presence of the marker compound of a standardized extract. A good lab technician will check the level of all known constituents but by failing to evaluate the levels of all known constituents, a company can still make a claim as standardized.

High doses of herbs as standardized extracts have their place in modern herbal medicine but not to displace the use of herbs in other forms. Because of their natural diversity it is impossible to categorically describe all herbs and herbal products as a single entity. The notion that there is only one chemical compound responsible for an herb’s action is similar to saying that there is only one compound that is useful in a specific food. Therefore an extract based on one or a number of presumed active constituents are highly questionable.

Extracts based on a predetermined marker extract, are less at issue and may offer substantial benefits in terms of identity and potency. However, unless such marker extracts are derived from the same high quality botanical sources as more conventional preparations, their quality may be compromised. The fact remains, that for both types of extracts there has been no studies confirming or denying their efficacy.

It is possible following good conventional manufacturing practices to simply make a stronger herbal concentrate that is not standardized to a marker compound. All extracts offer certain benefits but they also tend to increase the risk of adverse reaction so that the dose needs to be carefully regulated.

Other considerations may be at issue in an industry whose traditional consumer base has been among the most ecologically sensitive. While that is changing, it nevertheless remains ethically responsible to inform the public of the use of highly toxic and environmentally polluting compounds used in the preparation of certain herbal extracts.

What primarily began as a need for standardized herbal extracts for use in clinical trials, does not necessarily translate into these same extracts as being the best for normal usage. We might want to be a little more cautious in our effort to modernize herbs through the exclusive adoption of standardized extracts. For thousands of years herbalists have been using and prescribing herbs both singly as well as in complex formulas usually in the form of tea. Considering that we know little not only of the complex chemical compounds of plants themselves, but even less of their synergistic relationship to each other and how that may effect therapeutic activity, there is really no intrinsic need to abandon the use of other traditional formulations.


Pharmaprint has developed a process where standardized extracts can be made based on many markers. While this is commendable, it still begs the question of why and of what relevance is this to clinical herbal practice? Each herb processed in this way costs a minimum of $500,000 for each batch. They can then license these products to other manufacturers for resale. There is rumor that Nature’s Herbs is interested and one of the largest drug manufacturers, Centrum is putting six of these “superior” products in the market place this year, with six more scheduled for next year. Who will be able to afford Pharmaprint’s state of the art standardized extracts? Thus, the push is on. Pharmaprint is also creating prescription herbal drugs based on their process. Again, the effect will be to further devalue already demonstrated, quality non-chemically standardized products. At this point, it is difficult to access the potency and efficacy of these artificially standardized herbal products over whole, non-standardized herbs.

Michael Tierra, Founding Member of the American Herbalists Guild, California state licensed acupuncturist, herbalist, with an Oriental Medical Doctor degree. Author of several books including the best selling Way of Herbs (Pocket Books), The Way of Chinese Herbs, Planetary Herbology, Chinese Traditional Herbal Medicine and the East West Herbal Correspondence Course. He has an extensive website with articles, books, forums and chat room at www.planetherbs.com.

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