|
A Look Inside the Herbal
Industry
By Amanda Timberlake, M.S., R.D.
If you have ever visited a chiropractic expo, you are certainly no stranger
to the various herbs and supplements marketed toward DCs. As a chiropractor,
you may or may not choose to infuse herbs or nutritional supplements into your
practice. Regardless of your decision, it’s important as a health care
professional to have some understanding of the industry.
After observing a phenomenal expansion, the herbal industry is experiencing
slow to negative growth.1 This is probably
due to recent adverse publicity from toxicity reports including liver disease,
heart attacks and deaths. An example of negative press is an article titled,
“Dangerous Supplements: Still at large,” in the May, 2004 Consumer
Reports issue, which identified 12 potentially toxic herbs, designated “The
Dirty Dozen.”2 Some individuals
have blamed the herbal industry for its inability or meager attempts at self-regulation.
Despite what many scientists believed to be overwhelming data, the herbal industry
fought the FDA when the agency tried to regulate ephedra (Ma Huang). This defense
of ephedra seriously blemished the reputation of the herbal industry. Since
by the late 1990s, it was accepted by most researchers that the strokes, myocardial
infarctions, and deaths that were linked with ephedra consumption were not due
to pre-existing disease or massive dosing3,
which is what some in the industry were claiming.
Funding for Research
Despite the attrition of consumer confidence in herbs, many botanicals have
been shown to be efficacious. Advertising budgets are limited and others have
blamed the decline in herbal growth on the FDA and the scientific community
for demanding evidence based research. Their claim is that it is unreasonable
to expect the botanical industry to spend the money to study products that cannot
be patented. Herbs such as St. John’s wort, Ginkgo, and Saw Palmetto have
been shown to be effective in many clinical studies, yet have not gained support
from the medical profession nor have been endorsed by the FDA. Some view this
as a conspiracy to limit the herbal industry. In fact, many supplement consumers
continue to use supplements, despite scientific warnings against doing so, because
of their distrust of the medical and scientific profession.4
The Problems with Standardization
Many organizations have suggested the herbal industry should move toward standardization,
however, there are certain limitations. In a 2001 American Botanical Council
(ABC) editorial, the pros and cons of standardization were elucidated, and are
as follows:5
Positive aspects of standardization include its usefulness to help guarantee
quality and safety of herbs. Those active components of herbs, responsible for
their medicinal benefits would be referred to as “marker compounds.”
Being able to reproduce the “marker compound” of a supplement, each
time it is produced, would help herbs to maintain consistency. This would be
important for personal use and be required for quality clinical studies. Standardization
would necessitate careful, vigilant control of all raw materials and precise
manufacturing processes.
The problem with standardizations is that the activity of many herbs depends
on many chemical components and their interactions with each other. Focusing
on “marker compounds” may result in a “reductionistic”
view, minimizing the usefulness of the herbs. It is probable that the benefits
observed in many herbs result from the synergistic interactions of the plant
compounds, and not just one component. Using “marker compounds”
may also encourage companies to add these constituents to the original herb,
negating its “all natural status.” Standardization does not measure
potency, which would require a biological assessment. Despite these limitations,
standardization of herbs is warranted.
Product Consistency and Dosing
Herbal preparations include bulk herbs, teas, tinctures, fluid extracts and
tablets or capsules. These last two are typically in freeze dried or dehydrated
form. Unfortunately, there is often extreme variability in the over-the-counter
herbal supplements. An interesting study appeared in the Archives of Internal
Medicine in 20036. Ten herbs, (those
that had the highest sale dollars in 1998) were chosen from 20 different retail
stores in 2000. A variety of different brands were chosen from these stores
with the following breakdown: Echinacea (92), St. John’s wort (130), Ginkgo
Biloba (136), Garlic (143), Saw Palmetto (49), Ginseng (113), Goldenseal (142),
Aloe (45), Siberian ginseng (51) and Valerian (49). The number in the parenthesis
represents how many different products were evaluated for each herb. Product
consistency (or inconsistency as it turned out) was measured based on label
information. Adulterants and contaminants, often a problem in herbal supplements,
were not measured. The authors of this study devised a product label RDD (recommended
daily dose) of the herbs based on recommendations from The Professional’s
Handbook of Complementary and Alternative Medicines (2001). No mixed herb supplements
were evaluated.
The products studied varied considerably, despite being marketed as the same
herb, by ingredients listed, recommended daily dose and instructions for use.
Only 43 percent of the products reviewed were consistent in ingredients and
dosage. The more pricey botanicals were not necessarily better in terms of reliability.
The authors concluded that herbal products are not labeled in an accurate and
complete manner. Clearly, the results of this study would support a move toward
standardization.
Drug-Herb Interactions
Special groups, such as athletes, need to be especially aware of what is in
the herb supplements they are taking to avoid unwanted positive doping results.
Two studies presented in the International Journal of Sports Nutrition showed
why the lack of stardiazation and unclear labeling is a problem. Seventy-five
herb supplement products, most purchased through the Internet, were analyzed
for chemical composition.7 Seven of
17 (41 percent) of pro-hormones, contained different substances than indicated
on the labels. Unlabeled testosterone was present in several products. In another
study, data was collected from 160 elite athletes from 30 different sports.8
Seventy-seven percent of the subjects used at least one supplement, but most
of these athletes reported no or limited knowledge of what they were consuming.
One fourth of these athletes did not even check with International Olympic guidelines
before supplementing.
There is also a growing concern among health care providers that there is an
increasing occurrence of drug-herb interactions. Currently there are no warnings
listed on herbal labels. A recent study showed that 16 percent of all prescription
drug users were also using herbal supplements with possible “unintended”
interactions.9 Another study found
that half of the herbal consumers took a minimum of one prescribed medication
per day.10 Of special concern are the
potential adverse reactions with analgesic drugs. NSAIDS (non-steroidal anti-inflammatory
drugs), especially aspirin, have the potential to interact with those herbals
that have anti-platelet activity.11
These herbs include ginkgo, garlic, ginger, bilberry, dong quai, ferverfew,
ginseng, tumeric, meadowsweet and willow.11
Acetaminophen may also interact with gingko.11
Other drug-herb interactions that are of concern include: echinacea and hepatoxic
drugs; St. John’s wort and MAO inhibitors; valerian and barbiturates;
hawthorn or ginseng and digoxin; and licorice and certain BP medications.12
Herb supplement users are notorious for “forgetting” to tell their
health care provider that they take herb supplements. Because of this, pharmacies
are starting to develop a database for their computer patient records asking
customers what herbs, vitamins, and over-the-counter medications they use.13
This hopefully will reduce the amount of drug-herb problems consumers experience.
It is possible that some of the negative publicity surrounding herb-drug interactions
is undeserved. In a 2001 British Journal of Clinical Pharmacology article, the
authors evaluate the published scientific literature regarding the interactions
between herbal supplements and some common drugs.14
The authors developed a 10-point scoring system to assess the interaction probability.
They determined that 68.5 percent of the 108 cases of suspected interactions
had insufficient information to completely evaluate the herb-drug interaction/problem.
On November 4, 2004, the FDA announced major initiative for dietary supplements.
News of these proposed changes can be viewed at www.fda.gov/bbs/topics/news/2004/NEW01130.html.
Educating Yourself and Your Patients
Studies have shown that herb consumers are more likely to use their friends
and the media, including advertising, as their primary source of information
on the health effects of herbs.10 Supplement
users who accept as true the usefulness of supplements, do so regardless of
the scientific evidence, for or against.4
Chiropractors and other health care professionals need to take it upon themselves
to become educated on the pros and cons of herbal supplements (whether or not
they will ever recommend them). Books become outdated as soon as they hit the
shelves, necessitating constant perusal of the scientific literature. The ABC
publication, Herbalgram, is an excellent source for current botanical information.
Although slightly biased toward the herbal industry, all their articles seem
to be well referenced. They also summarize current peer reviewed articles on
herbs and health (both pro and con). A Herbs in Health class is offered in the
nutrition curriculum at Life University, and many chiropractic students take
advantage of this opportunity to learn about herbal evidence-based research.
(If you live in the metro Atlanta area this class can be audited this winter
for only $100.) If you’re interested in reading more articles related
to herbs, let us know at editor@todayschiropractic.com.
Amanda Timberlake is an associate professor in the nutrition program at
Life University in Marietta, Ga. She has been a registered dietitian for more
than 20 years and has experience in dietetics, community nutrition, food service
and wellness. Timberlake has been lecturing at Life University for 14 years
and started her own seminar business in 2001.
References
© Copyright 2005 Today's Chiropractic