Some Americans May Get Too
Many Nutrients
By
LiveScience Staff
Amid
concern that some people take too many dietary
supplements, the National Institutes of Health
today released preliminary recommendations that
generally urge caution.
The
statement from the agency, part of the U.S. Department
of Health and Human Services, concerns multivitamin
and mineral supplements, collectively called MVMs.
Conclusions were reached by a 13-member independent
panel working for the agency.
"Half
of American adults are taking MVMs and the bottom
line is that we don't know for sure that they're
benefiting from them," said J. Michael McGinnis,
chair of the panel from the Institute of Medicine
of the National Academy of Sciences, who chaired
the panel. "In fact, we're concerned that
some people may be getting too much of certain
nutrients"
The
findings pertain to the generally healthy population
and do not include pregnant women, children, or
those with disease.
The
panel recommends:
* Combined use of calcium and vitamin D supplementation
for postmenopausal women to protect bone health.
*
Anti-oxidants
and zinc should be considered for use by non-smoking
adults with early-stage, age-related macular degeneration,
an eye condition that can cause blindness.
*
Women of childbearing age should take daily folate
to prevent birth defects of the brain and spinal
cord.
The
researchers found no evidence to recommend beta
carotene supplements, a form of vitamin A, for
the general population, and strong evidence to
caution smokers
aagainst taking them. Beta-carotene has been linked
to an increase in lung cancer among smokers who
took it regularly.
In
looking specifically at MVMs for chronic disease
prevention, the panel found that the available
data are insufficient to make a firm recommendation
for or against their use in the general population.
Health
conscious people are the most likely to consume
MVMs, which makes it difficult to determine whether
MVMs, exercise, diet or other factors are responsible
for their good health, the panel concluded.
Despite
the general pubic perception that MVMs are safe,
the panel identified several possible risks. Too
much of certain nutrients can have adverse effects,
the scientists said. And the combined effects
of eating fortified foods, taking MVMs, and consuming
single vitamins or minerals in large doses can
lead to overconsumption.
The
panel urged changes in the regulation of MVMs
and other dietary by the Food and Drug Administration
(FDA). Specifically, the panel recommended that
Congress expand FDA's authority and resources
to require manufacturers to disclose adverse events,
to ensure quality production, and to facilitate
consumer reporting of adverse events by including
reporting information on dietary supplement labels.
The
panel included experts in the fields of food science
and human nutrition, biostatistics, biochemistry,
toxicology, geriatric medicine, family medicine,
pediatrics and pediatric endocrinology, cancer
prevention, epidemiology, disease prevention and
health promotion, and consumer protection.
*
Vitamin Mania: The Truth
about Antioxidants