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Dietary Supplements—Are They Safe?
According to the Dietary Supplement and Education Act (DSHEA) of 1994, a
dietary supplement is a product taken by mouth that contains an
ingredient intended to supplement the diet such as vitamins, minerals,
herbs or other botanicals, amino acids, and substances such as enzymes,
organ tissues, glandulars, and metabolites. Dietary supplements are
considered foods and not drugs. Supplements come in every imaginable
form including teas, powders, tablets and capsules. According to the
National Institutes of Health (NIH), some 24,000 to 30,000 products are
currently on the market. These products are sold in pharmacies, health
food stores and grocery stores, over the internet and in physician’s
offices. The Food and Drug Administration (FDA) reported that in 2004,
millions of Americans took dietary supplements, accounting for $3.2
billion dollars in sales.
Most Americans believe that dietary supplements offer health benefits
and assume they cause no serious harm. This is true in most cases, but
the dangerous effects of some have been well known for more than a
decade. Several products available in the United States have been banned
in other parts of the world including Asia, Europe, and Canada. The FDA
oversees safety, manufacturing and product information. The NIH
coordinates research on dietary supplements. According to the American
Medical Association, however, supplements are “virtually unregulated”
and there is no central source of information about adverse reactions to
supplements. While drug manufacturers are required to prove their
products are safe before being marketed, DSHEA makes the FDA prove that
supplements on the market are unsafe. FDA’s job is difficult because
manufacturers are not required to report adverse events, very little
information is available about the safety record of most supplements and
the standards to demonstrate that a supplement is hazardous are very
high.
Supplements do not have to be tested for safety or efficacy, nor do they
have to be approved by the FDA before they can be sold to the public.
Almost all supplements can produce some unpleasant side effects. Warning
labels on a supplement’s potential side effects are not required, even
for products with known serious hazards. There is no assurance that the
contents of a supplement are pure and provided in the quantities stated
on the label. Contaminants are routinely found in supplements.
Supplements are often sold under a variety of names and sold in
combinations without all ingredients listed. Many have the perception
that because dietary supplements are natural, they are safe. In reality,
many act like drugs and have similar risks. The FDA has recorded more
than 2,500 reports of side effects and 79 deaths associated with dietary
supplements. In addition, the NIH has identified side effects in some
supplements that raise fitness for duty concerns. For example, Kava and
Valerian are listed as having drowsiness and dizziness as side effects.
In May 2004, a Consumer
Reports article, “Dangerous Supplements: Still At Large,”
identified twelve supplements that should be avoided and
listed long-term effects of some herbal remedies that are
easily obtainable. The article can be found at
www.consumerreports.org/main/display_report.jsp.
The unsafe supplements listed are the following.
1. Androstenedione, increases cancer risk and decreases HDL
Cholesterol;
2.
Aristolochic acid, an herb conclusively linked to kidney
failure, cancer and, death;
3.
Bitter Orange, a stimulant similar to Ephedra, linked to
high blood pressure,
increased risk of heart arrhythmias, heart attack and
stroke;
4. Chaparral, linked to often irreversible abnormal liver
function or damage, death;
5. Comfrey, linked to often irreversible abnormal liver
function or damage, death;
6. Germander, linked to often irreversible abnormal liver
function or damage, death;
7.
Kava, linked to occasionally irreversible abnormal liver
function or damage, death;
8.
Lobelia, linked to breathing difficulty, rapid heartbeat,
low blood pressure, diarrhea,
dizziness, tremors, and death;
9. Organ/glandular extracts, theoretical risk of mad cow
disease, particularly from brain extracts;
10. Pennyroyal Oil, linked to kidney and liver failure,
nerve damage, convulsions, abdominal
tenderness, burning of the throat, and death;
11. Scullcap, linked to abnormal liver function or damage;
12.
Yohimbe, a sexual stimulant linked to change in blood
pressure, heart arrhythmias, respiratory
depression, hearth attack and death. |
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Where to Find? .....
FTA Drug & Alcohol Discussion Forum:
http://transit-safety.volpe.dot.gov/
Safety/BBS
Drug and Alcohol Audit Questions:
http://transit-safety.volpe.dot.gov/
Safety/DATesting/Audit
The information presented on this
page should be used to update Chapter 5 of the revised Implementation
Guidelines. |