Antioxidant defenses also operate synergistically. For example, a number of
carotenoids working together have higher anticancer properties than a single
carotenoid. Thus beta-carotene supplements may not provide the same protection as
eating fruits and vegetables rich in beta-carotene. Other substances in the plant may
help the body to assimilate its benefits as well as buffer any side effects. Including
the whole plant in the final product often ensures that some measure of the natural
“checks and balances” will be retained.
Various herbs and other substances may also work synergistically with one another.
A rather dramatic example of this effect occurred during the testing of plant samples
from the rain forest of Ecuador for chemicals that could be used to treat diabetes.
The leaves from the plant were immersed in an alcohol extract and then a water
extract. The debate among the researchers concerned whether to throw a live crab
into the extract, just as native healers did. Some believed it might make a difference
while others believed the crab was simply ritualistic. Amazingly, the only extract
that showed therapeutic effect was the one with the crab in it. It turns out that a
component in a crab’s shell is needed to extract the active chemical compound from
the plant.
Safety.
Not all plant life is beneficial. Most plant-related poisonings are due to accidental
consumption of toxic ornamental plants such as jade, holly, poinsettia, schefflera,
philodendron, and dieffenbachia rather than from herbs. Data compiled by the
American Association of Poison Control Centers indicates that in any two-year
period of time, plants cause two or three deaths and approximately 50 major poi-
sonings. In contrast, prescription medications cause close to a thousand deaths from
poisoning and almost 7,000 major nonfatal poisonings per year. Unrelated to direct
poisoning are adverse drug reactions (ADRs), defined as any unintended and unde-
sired effect of a drug with usual therapeutic doses. After excluding errors in drug
administration, noncompliance, overdose, and drug abuse, a significant study found
that ADRs may be the fourth to sixth leading cause of death in the United States.
This incidence has remained stable over the past 30 years, a fact not widely recog-
nized by the general population.
The vast majority of herbal medicines present no danger. Some can, however, cause
serious side effects if taken in excess or, for some, if taken over a prolonged period of
time. For example, comfrey, a digestive remedy, and coltsfoot, used to treat cough,
can cause liver damage if taken in large doses. Herbs can also interact with drugs,
and caution should be used when combining herbs with prescription and OTC med-
ications. With the exception of mild herb teas, pregnant women should not take
herbs internally.
CHAPTER 6 HERBAL MEDICINE 89
