The makers
of a new vitamin E antioxidant supplement claims it is 20 times more powerful
than existing vitamin E products in protecting the heart, but not all researchers
are convinced of the vitamin's benefits.
Phoenix- based
Bionutrics Inc. says its Vitenol E 20/20 contains all eight standard isomers
of vitamin E together with phytosterols, which are not found in standard
vitamin E supplements.
The compound
product is based on tocotrienol, one of several fractions of the vitamin.
But the evidence
does not currently support any additional benefit of compound vitamin E
over the single isomer, called alpha-tocopherol, said Jeffrey Blumberg,
chief of the antioxidant research laboratory at Tufts University, Boston.
"Although this
is a controversial area, the data remain equivocal," he told United Press
International in a telephone interview. "As of last year, the redefined
dietary requirement for vitamin E, issued by the Institute of Medicine,
is specific for only one vitamin E isomer, so-called natural source alpha-tocopherol.
"Prior to that
we looked at the vitamin E isomers as a group," he continued. "We know
now that humans only use one isomer, and any product that boasts of multiple
vitamin E isomers is ignoring the science."
Howard
Schneider, president of LipoGenics, Inc., a Bionutrics subsidiary, said,
"The importance of alpha-tocopherol vitamin E for cardiovascular health
is well recognized within the health and medical communities."
He added, "However,
alpha-tocopherol vitamin E is not a highly potent antioxidant, nor does
it exhibit many benefits of the other vitamin E isomers. Alpha-tocopherol
vitamin E, therefore, requires relatively high doses to provide its limited
beneficial health effects."
According to
the American Heart Association, high intake of vitamin E has been associated
with a decreased risk of coronary artery disease incidence, while animal
studies suggest that vitamin E can slow the development of atherosclerosis.
Ronald Lane,
president and chief executive officer of Bionutrics, told UPI that the
benefits of vitamin E in general on cardiovascular health have been demonstrated
in hundreds of studies. One placebo-controlled study found that heart attack
patients taking between 800 and 1,200 milligrams of vitamin E had a 77
percent lower risk of a second heart attack, he noted.
But earlier
this month, researchers at the University of Pennsylvania reported in the
Journal of the American Medical Association that high doses of vitamin
E had little effect on reducing oxidative stress in a group of 30 healthy
people.
"The average
Western diet provides the recommended daily allowance of vitamin E,"
concluded study investigators Drs. Emma Meagher, and Garret FitzGerald.
"We found no evidence of additional effects of supplementing these individuals
with a range of dosages of vitamin E on their
rate of lipid peroxidation."
Tufts' Blumberg
also said he does not trust comparison ranking of vitamins, and that any
claim that a vitamin will work "20 times better is suspect."
"I'd like to
see their research," he said. "Personally, as an antioxidant researcher,
I have never liked potency rankings because vitamins don't act alone. You
can say a general is more important than a private, but you wouldn't send
a general into battle without a private. The same is true with
vitamins."
In recent years
vitamin E has become one of the most popular vitamins at health stores,
representing a $1 billion market in the United States. Prior to the 1920s
it was viewed as nonessential to humans. Today, however, recent studies
have shown conflicting results as to the vitamin's effect as a supplement.
Vitamin E is
believed to protect the body against oxygen, which has a tendency to form
compounds that can contribute to the development of heart disease, cancer,
and other degenerative diseases. This is where vitamin E and other antioxidants
come into play: they all help keep oxidized fat cells in the body from
collecting against the lining of arteries.
Although a number
of studies have shown this beneficial effect on patients with heart disease,
it remains unclear whether healthy persons can avert cardiovascular problems
by taking vitamin E.
Carey Ainsworth
Wright, at the FDA's Center for Food Safety and Applied Nutrition, stressed
that all persons should check with their health care provider before taking
any new dietary supplements. Unlike prescription drugs, the agency does
not "approve" diet products, but is authorized to investigate health claims
and consumer complaints about products sold for health purposes.
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2001 by United Press International.
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