The advent of herbal products in the form of standardized extracts was initiated in 1992 as a result of a European Guaranteed Potency law. Since that time, proponents have heralded standardized herbal extracts as a major historical advance, allowing both consumers and medical doctors to use herbal products with greater confidence and more consistent results. What most don�t realize, however, is that the majority of these advocates consist of:
1. academics and medical doctors who often have little personal or clinical experience with herbs,
2. researchers whose work is funded by drug companies that manufacture the standardized extracts used in their clinical trials, and
3. naturopathic physicians who have financial ties with the companies that produce these products.
One group noticeably lacking from the chorus of standardized extract enthusiasts is professional clinical herbalists who rely on herbs as their primary healing modality. While not categorically condemning standardized extracts, clinical herbalists agree that just because an herb is biochemically standardized, it is not automatically more potent or efficacious than a non-standardized extract.
Standardized Herbal Extracts - What Are They?
Standardized herbal extracts are of two main types: An active constituent extract where there is a known and accepted active biochemical principle, and a marker extract where the active biochemical principle is not known and a characteristic compound is used as a "marker," which signifies the presence of the other biochemical compounds that give the herb its therapeutic properties.
In an active constituent extract, the known biochemical compound is isolated from the herb and concentrated to an amount not naturally found in the plant. Think of caffeine from coffee or morphine from the opium poppy. This type of extract tends to be more drug-like, potentially having undesirable side effects not normally present in the herb or its non-standardized extract.
From the herbalist�s perspective, this type of extract, while stronger in intended action is more of an herbal drug or "phytopharmaceutical" as it is called in Europe. As such, when the isolate is manipulated at the expense of the whole herb�s constituents, one may lose other properties contained within the herb, as well as buffering compounds that may lessen adverse reactions.
Examples of herbs where the known active principle is treated as an isolate include:
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) and kava (30-40% kavalactones).
In a marker extract, no single active constituent is known, so the entire extract is treated as active and all plant constituents are present. With this type of extract, the caffeine in the above example would not be used as the marker compound because it is not unique enough to any one plant. When the ginsenosides of ginseng, for example, are standardized from 5 to 15 percent, all other properties of the herb are present in a marker extract. In the case of ginseng, however, the herb�s strength depends greatly on its age and growing conditions. So the mere presence of a fixed percentage of ginsenosides does not guarantee the tonic properties of a well-aged root. In fact, since ginsenosides are also found in the cheaper leaves, some standardized ginseng extracts are made only with ginseng leaf rather than the root.
Examples of herbs where the active principle is either not known or not treated as an isolate include:
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. John�s wort (0.3-0.5% hypericin), schisandra (2.6-4% schisandrins), valerian (0.8-1% valerenic acid) and willow (8% salicin).
While these represent the most widely used categories, science continues to develop further methods. One created by PharmaPrint Inc. is able to identify and standardize several active constituents. Their process represents the cutting edge of standardization, but with a cost of more than $500,000 per herb is only feasible for the most vested of pharmaceutical companies. They ultimately plan to make pharmaceutical-grade herbal products for the use of medical doctors and pharmacists.
Science versus Tradition
Traditional clinical herbalists use herbs not so much to treat named diseases, but to implement a shift in underlying physiological processes so the body can heal itself. The body�s complex processes can be affected by herbs, drugs, foods, emotional experiences and therapeutic exercises. This alone delineates a fundamental difference between wholistic herbal medicine and the phytotherapeutic or symptomatic drug-like approach of phytotherapy. While neither is fully exclusive of the other, the difference is in the intention of the final therapeutic goal.
Does this mean that one shouldn�t try an herb such as St. John�s wort for mild depression? Certainly not, but herbal medicine�s strength is its capacity to effectively treat based on the individual needs of each patient. The phytotherapist, on the other hand, uses herbs to treat specific named diseases. For this purpose, standardized extracts based on identified chemical constituents are appropriate. However, the fact that standardized garlic is sold for reducing cholesterol and hawthorn for reducing hypertension does not make them the best herbs in all cases. If you are not using the right herb for an individual�s condition and constitution, it makes no difference whether it is a high-priced standardized extract of guaranteed potency or a more traditional preparation of the same herb.
Industry "Standards"
There is no universally accepted "standard" for the manufacture of standardized herbal extracts. Companies manufacturing methods may vary so widely their finished products hardly resemble each other. Extracts may not be consistently standardized to one marker. For instance, nettle root is standardized by one company to 5% amino acids, by another to 8% sterols, and yet a third to 35ppm (parts per million) scopoline. Echinacea can be standardized to three different constituents: echinocosides, polysaccharides or polybutylides. And what is considered an active compound for any given herb may change in time, such as the hyperforin of St. John�s wort recently understood to be more active than its previous marker, hypericin.
As with decaffeinated coffee, the manufacture of high isolate standardized extracts may also involve highly toxic solvents such as hexane, benzene, methyl chloride or acetone. Besides leaving minute residue in the finished product, these solvents have hazardous effects on the environment.
Finally, on average, the comparison for the cost of standardized extracts over their non-chemically standardized counterpart is more than double that of the standardized version of the same herb.
Pharmaceutical Takeover of the Herbal and Vitamin Industry
With the development of standardized extracts, pharmaceutical companies are able to obtain exclusive international patents on isolated herbal constituents, as well as on the process of manufacturing them. Standardization may not mean better herbal medicine, but it does mean higher costs and more profits to pharmaceutical companies who can afford research that will guarantee them exclusive rights to these extracts.
This issue of error and deception has been reported down through the ages. According to veteran herbalist James Duke, herbal extracts have been "spiked" to deceptively indicate the presence of a specific marker with little or none of the herb�s associated constituents. In other words, except for the marker compound, there may be a completely different herb or no herb at all present. Therefore, while standardized extracts may offer a degree of assurance that the product is what it claims to be, it is still possible to be deceived.
Science does not exist in a vacuum, as medical and herbal research is dependent upon funding from business and industry. As long as science is influenced by the bottom line, truth will be threatened. The danger for herbs is that the public will be misled to accept primarily scientifically manufactured products that will eventually be superseded by "more effective chemical drugs."
So the questions remain: Is the exclusive sale of herbs in the form of standardized extracts a Trojan horse, bringing increased adverse reactions, increased governmental regulation and intervention, and ultimately the availability of only a few herbs deemed financially expedient to standardize by multinational pharmaceutical companies?
