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ScienceWeek
PUBLIC HEALTH: HEAVY METALS IN AYURVEDIC HERBAL MEDICINES
The following points are made by R.B. Saper et al (J. Am. Med. Assoc. 2004 292:2868):
1) Ayurvedic medicine originated in India more than 2000 years ago and relies heavily on herbal medicine products (HMPs).[1] Approximately 80% of India's 1 billion population uses Ayurveda through more than one-half million Ayurvedic practitioners working in 2860 Ayurvedic hospitals and 22,100 clinics.[2] Ayurved's popularity in Western countries has increased.[3] In the US, Ayurvedic remedies are now available from South Asian markets, Ayurvedic practitioners, health food stores, and the Internet. Because Ayurvedic HMPs are marketed as dietary supplements, they are regulated under the Dietary Supplement Health and Education Act (DSHEA), which does not require proof of safety or efficacy.[4]
2) Herbs, minerals, and metals are used in Ayurvedic HMPs.[2] Lead toxicity has been associated with use of Ayurvedic HMPs, including status epilepticus,[5] fatal infant encephalopathy, congenital paralysis and sensorineural deafness, and developmental delay. Since 1978, at least 55 cases of heavy metal intoxication associated with Ayurvedic HMPs in adults and children have been reported in the US and abroad.[5]
3) Although Ko (1998) raised concern about heavy metals in traditional Chinese medicines available in California, no studies have specifically measured heavy metals in Ayurvedic (traditional Indian) HMPs sold in the US. The authors determined the heavy metal content in a sample of Ayurvedic HMPs sold in Boston-area retail stores. The authors also estimated daily heavy metal intakes for each HMP and compared these with maximum allowable regulatory standards.
4) The authors conclude: One-fifth of Ayurvedic HMPs produced in South Asia and available in Boston South Asian grocery stores contains potentially harmful levels of lead, mercury, and/or arsenic. Users of Ayurvedic medicine may be at risk for heavy metal toxicity, and testing of Ayurvedic HMPs for toxic heavy metals should be mandatory.
References (abridged):
1. Chopra A, Doiphode VV. Ayurvedic medicine: core concept, therapeutic principles, and current relevance. Med Clin North Am. 2002;86:75-89
2. Gogtay NJ, Bhatt HA, Dalvi SS, Kshirsagar NA. The use and safety of non-allopathic Indian medicines. Drug Saf. 2002;25:1005-1019
3. Hontz J. Balm from the East: the effectiveness of the ancient Indian healing art of Ayurveda is getting a closer look in the U.S. Los Angeles Times. January 26, 2004:sect F:1
4. Marcus DM, Grollman AP. Botanical medicines: the need for new regulations. N Engl J Med. 2002;347:2073-2076
5. Centers of Disease Control and Prevention. Lead poisoning associated with use of Ayurvedic medications--five states, 2000-2003. MMWR Morb Mortal Wkly Rep. 2004;53:582-584
J. Am. Med. Assoc. http://www.jama.com
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MEDICAL BIOLOGY: QUACK MARKETING OF INTERNET HERBAL PRODUCTS
The following points are made by C.A. Morris and J. Avorn (J. Am. Med. Assoc. 2003;290:1505-1509):
1) The Dietary Supplement Health and Education Act passed in 1994 restricted the Food and Drug Administration's (FDA's) control over dietary supplements, leading to enormous growth in their promotion.(1) Between 1990 and 1997, use of herbal remedies increased 380% in the United States.(2) Data from a 1998-1999 survey estimated that 14% of US adults took herbal supplements and approximately 1 in 5 adults taking prescription medications also used an herbal or dietary supplement.(2,3) In less than a decade, the dietary supplement industry has assumed a substantial proportion of the health market, grossing nearly $18 billion in 2001.(4)
2) The Dietary Supplement Health and Education Act and other more recent regulations(5) defined several types of labeling claims for dietary supplements. To satisfy regulatory requirements, claims that describe a relationship between a supplement and a particular condition or disease must be preapproved by the FDA and, similar to drug approval, would entail submission of evidence to substantiate the claims. In contrast, structure or function claims are not preapproved and can be made without submission of substantiating data. However, structure or function claims cannot mention specific diseases and must be accompanied by a standard disclaimer: "This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease." Only drugs can be characterized by statements about disease treatment or prevention and require more stringent FDA approval after a thorough review of available evidence concerning efficacy and safety based on randomized trials. Despite these regulations, there is growing concern in the medical community that the existing legislation inadequately protects consumers from herbal product claims.
3) Herbal products are commonly marketed on the Internet, which was used by approximately 140 million individuals in the US in 2001. According to the Pew Internet Project for Health, 62% of individuals who used the Internet in 2002 sought health information, with approximately half seeking information on alternative and complementary therapies. More than half of the Pew survey respondents said they thought "almost all" or "most" online health information they encountered was credible, and only 25% said they routinely scrutinize a health-related Web site's information, references, and sources. More than 4 of 5 Internet users used commercial search engines for their search.
4) Although the nature of Internet claims for specific products or diseases has been examined, few investigators have systematically analyzed information consumers would find through commonly used Internet search engines. The authors conducted an analysis of Internet Web sites to assess the nature of marketing claims for the 8 best-selling herbal products.
5) The authors provide the following sample disease claims from herbal product web sites:
a) Ginkgo Biloba: "Its effects in improving circulation also contribute to its use for impotency and peripheral vascular insufficiency... Ginkgo treats depression, headaches, memory loss and ringing in the ears (tinnitus). It is also recommended for Alzheimer's, asthma, eczema, heart and kidney disorders."
b) St John's Wort: "St John's wort is effective in the treatment of mild to moderate depression... recent studies have shown that it could have a potent anti-viral effect against enveloped viruses."
c) Echinacea: "Because it has natural antibiotic actions, Echinacea is considered an excellent herb for infections of all kinds. In addition, it works to boost lymphatic cleansing of the blood, enhances the immune system and has cortisone like properties which contribute to its anti-inflammatory action. It is recommended for stubborn viral infections, yeast infections and for arthritic conditions."
d) Ginseng: Q: "(I have) high blood pressure (170/90). Will American ginseng lower blood pressure and if so, how much should one take and how long before results show?" A: "While American Ginseng will help, we have a combination product that will do a much better job. Look at product #1960 American Ginseng/Garlic/Tien Chi. This is a great product... It is potentially beneficial for AIDS, radiotherapy, and chemotherapy patients, as it reduces the side effects of toxic drugs by increasing red and white blood cell counts. Dang Shen is given for breast cancer, asthma, diabetes, heart palpitations, memory or appetite loss and insomnia."
e) Saw Palmetto: "The lipophilic extract of the saw palmetto (ser repens) berries is the most widely used herbal preventive and therapeutic agent for benign prostatic hyperplasia (BPH)."
f) Kava Kava: "It is a valuable urinary antiseptic, helping to counter urinary infections and to settle an irritable bladder... Kava kava's analgesic and cleansing diuretic effect often makes it beneficial for treating rheumatic and arthritic problems such as gout."
g) Valerian Root: "The herb valerian is most effective in treating a wide range of stress conditions such as irritability, depression, fear, anxiety, nervous exhaustion, hysteria, delusions, and nervous tension... The herb is useful for treating shingles, sciatica, neuralgia, multiple sclerosis, and epilepsy."
6) The authors conclude: "Consumers may be misled by vendors' claims that herbal products can treat, prevent, diagnose, or cure specific diseases, despite regulations prohibiting such statements. Physicians should be aware of this widespread and easily accessible information. More effective regulation is required to put this class of therapeutics on the same evidence-based footing as other medicinal products."
References (abridged):
1. Dietary Supplement Health and Education Act. Pub L No. 103-417, 108 Stat 4325 (codified at 21 USC 301 [1994])
2. Eisenberg DM, Davis RB, Ettner SL, et al. Trends in alternative medicine use in the United States, 1990-1997. JAMA. 1998;280:1569-1575
3. Kaufman DW, Kelly JP, Rosenberg L, et al. Recent patterns of medication use in the ambulatory adult population of the United States. JAMA. 2002;287:337-344
4. NBJ's annual industry overview VII. Nutrition Business Journal. May/June 2002:1-48
5. US Department of Health and Human Services, US Food and Drug Administration. Regulations on statements made for dietary supplements concerning the effect of the product on the structure or function of the body; final rule, 65 Federal Register. 1000 (2000) (codified at 12 CFR 101)
J. Am. Med. Assoc. http://www.jama.com
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ON THE EFFICACIES AND CONFUSIONS OF ALTERNATIVE MEDICINE
Notes by ScienceWeek:
What is called "alternative" medicine, and which consists of medical practices outside the mainstream of "official" medicine, has always been a significant part of the health care of the public, involving healers, herbalists, bonesetters, barbers, shamans, spiritualists, homeopaths, psychic and magnetic healers, and so on. It is estimated that in the US 40 percent of the population makes use of medical procedures outside of what is considered orthodox medical practices.
P.B. Fontanarosa and G.D. Lundberg (J. Amer. Med. Assoc. 1998 280:1618) make the following points:
1) There is no alternative medicine. There is only scientifically proven, evidence-based medicine supported by solid data, or there is unproven medicine, for which scientific evidence is lacking. Whether a therapeutic practice is "Eastern" or "Western", is unconventional or mainstream, or involves mind-body techniques or molecular genetics is largely irrelevant except for historical purposes and cultural interest.
2) In the US and throughout the world, most alternative therapies have not been evaluated using rigorously conducted scientific tests of efficacy based on accepted rules of evidence. The lack of properly designed and conducted randomized trials is a major deficiency... However, some advocates of alternative medicine argue that many alternative therapies cannot be subjected to the standard scientific method, and thus instead must rely on anecdotes, beliefs, theories, testimonials, and opinions to support effectiveness and justify continued use.
3) For alternative medicine therapies that are used by millions of patients every day and that generate billions of dollars in health care expenditure each year, the lack of convincing and compelling evidence concerning efficacy, safety, and outcomes is unacceptable and deeply troubling.
4) Until solid evidence is available that demonstrates the safety, efficacy, and effectiveness of specific alternative medicine interventions, uncritical acceptance of untested and unproven alternative medicine therapies must stop. Alternative therapies that have been shown to be of no benefit (aside from possible placebo effects) or that cause harm should be abandoned immediately. Physicians, insurance plans, medical centers and hospitals, managed care organizations, and government policy-makers should base decisions regarding incorporation of and payments for alternative medicine therapies on evidence-based research and objective cost-effectiveness analyses rather than on consumer interest, market-demand or competition, well-publicized anecdotal reports, or political pressures from well-organized and influential interest groups. [Editor's note: The Fontanarosa-Lundberg editorial briefed here is a commentary on 6 studies of the efficacy of alternative medicine appearing in the same issue of the journal.]
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