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The ads are all over the place, promising to
take years off your face and restore your youthful vitality.
Just try TV surfing after midnight, especially on a slow news
day — you can’t miss the rehearsed testimonials
from people who claim to be stronger and healthier after consuming
Brand Whatever “magical potion.”
There are many ingredients in these
anti-aging concoctions, but the one that seems to generate
the most marketing buzz is growth hormone, a naturally occurring
substance that manufacturers are now selling in a bottle.
Human growth hormone (HGH) is essential
to growth, especially for children. It’s a protein produced
in the pituitary, a small gland buried deep within the brain.
HGH is involved with a variety of functions, including normal
growth, sexual function, bone strength, maintaining energy
levels, protein formation and tissue repair. HGH therapy is
nothing new. In fact, doctors have used it to successfully
treat children suffering from certain conditions — such
as growth-hormone deficiency, kidney disease, Prader-Willi
syndrome and Turner’s syndrome—that prevent them
from growing normally. HGH has also been used sparingly and
with mixed results in adults to treat growth failure and weight
loss caused by AIDS.
But before you reach for that bottle
of HGH, a word of warning. A new study conducted by the National
Institutes of Health and other centers suggests that not only
do the benefits of growth hormone fall far short of its hype
but that the substance may pose significant risks, as well.
The study — published this week in The Journal of the
American Medical Association — involved 131 healthy
seniors between the ages of 65 and 88. Each participant was
randomly assigned to four treatment groups: growth hormone
plus a sex steroid (testosterone for men; hormone-replacement
therapy for women); growth hormone plus a placebo; inactive
growth hormone plus an active sex steroid, or both inactive
growth hormone and sex steroid.
At the end of the 26-week study,
women on growth hormone had gained an average of two to five
pounds of muscle and lost about five pounds of fat. Similar
results were found in men on growth hormone, who gained seven
to 10 pounds of muscle and shed about the same amount of fat.
These were modest gains, but it still left the important question:
what was the impact on each participant’s daily functioning?
The answer: minimal at best.
Only one of the groups experienced
any real improvement in this regard. Those men who had taken
both growth hormone and testosterone showed small increases
in endurance and strength. They boosted their cardiovascular
endurance by 8 percent and increased their muscle strength
by 7 percent, though the researchers note that statistically,
this last improvement was of borderline significance.
Another concern is the side effects.
In this study, these included swelling of the arms and legs,
carpal-tunnel syndrome (tingling and numbness of the hand),
joint pain, breast swelling and headaches. Diabetes or the
impaired ability to process sugar adequately are also potential
side effects.
So should consumers buy products
containing HGH? Participants in the latest study were taking
prescription HGH injections that were 10 or more times more
potent than most products sold over the counter. In fact,
most products available without a prescription don’t
contain much HGH at all because FDA rules say that the hormone
can only be given at the mandate of a physician. However,
if the product contains a small amount of HGH mixed with other
ingredients it’s classified as a dietary supplement,
not a drug, and thus isn’t subject to the same approval
process and scrutiny as the “real” HGH.
There’s also the issue of whether
what you think you’re buying is actually the real thing.
The companies that make these tonics use different methods
of preparation: some may use animal products; others employ
a recombinant DNA technique that uses the bacteria E. coli
to synthesize their product. Then there are some products
that don’t even contain HGH, but herbal products that
are similar in function. Checking the label of these products
is key, as most will list their active ingredients. If you’re
unsure which form of HGH is in the product, it’s best
to get answers from the company or an independent health authority
before using it.
Anyone considering growth hormone
as a way to turn back the clock should ask whether it is worth
risking these potential problems for debatable and relatively
small gains. Growing old is a phrase that, unfortunately,
has almost become taboo in our society, perpetually fueling
our hunt for the fountain of youth. But whatever those flashy
ads might be saying, that search is far from over.
By
Dr. Ian Smith
© 2002 Newsweek, Inc., Nov. 13, 2002
Dr. Ian Smith is the medical correspondent for NBC News
and the author of “The Take-Control Diet” and
“Dr. Ian Smith’s Guide to Medical Websites.”
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