Wednesday, May 24, 2006

New NIH Report on Vitamin Supplements

A new report on Multivitamins by the NIH suggests that most people who take multivitamins already consume sufficient amounts of vitamins and minerals and do not need to supplement with additional amounts of them. They have also suggested that taking vitamins and minerals in excess (beyond the RDA level) can be problematic.

However, the report did point out some positive aspects of vitamin supplementation, specifically that of folic acid.

Dr. Stephen Barrett's newsletter summarized the report in the following manner.
Comprehensive dietary supplement reports issued.

The National Institutes of Health has drafted a
"state-of-the-science" report about whether multivitamin/mineral
supplements (MVMs) and certain single nutrient supplements can
prevent chronic disease. The conclusions expressed by the report's
authors include:

**More than half of American adults take MVMs with the belief that
they will feel better, have greater energy, improve health, and/or
prevent and treat disease.

**Compared with nonusers, supplements takers tend to have a better
diet, less need for supplements, and more risk of exceeding the safe
upper limit (UL) of some nutrients.

**There is insufficient evidence to recommend either for or against
the use of MVMs by the American public to prevent chronic disease.

**Few high-quality studies have addressed whether one or a few
nutrients can prevent chronic disease in American adults, and only a
few such studies have yielded positive results.

**With few exceptions, neither beta-carotene nor vitamin E had
benefits for preventing cancer, cardiovascular disease, cataract, and
age-related macular degeneration. Beta-carotene supplementation
increased lung cancer risk in smokers and persons exposed to asbestos.

**Folic acid alone or combined with vitamin B12 and/or vitamin B6 had
no significant effect on cognitive function.

**Selenium may confer benefit for cancer prevention but not
cardiovascular disease prevention.

**Calcium may prevent bone mineral density loss in postmenopausal
women and may reduce vertebral fractures, but not non-vertebral
fractures. The evidence suggests dose-dependent benefits of vitamin D
with or without calcium for retaining bone mineral density and
preventing hip and other nonvertebral fractures.

**The FDA lacks the resources to collect adequate data and lacks the
legal authority to safely regulate the dosage of individual
ingredients.

**Additional research and a mandatory adverse-event reporting system
are needed for dietary supplements.

The draft statement
http://consensus.nih.gov/2006/MVMDRAFT051706.pdf
was accompanied by a 321-page evidence report.

A final statement is expected in July.

So, what is the solution? In the past, scientists have advised adding certain essential vitamins and minerals to food products, such as folic acid to breakfast cereals and iodine in salt, to solve chronic deficiencies which have been very successful. However, if most people who take multivitamin supplements don't need to be, as the NIH indicates, then what is the solution for those who aren't? Perhaps schools could give out vitamin and mineral supplements with school food programs which are already subsidized. Or possibly enriching more foods is the answer. For now, it is hard to say, but for those of us who already take a multivitamin supplement, we may want to rethink the levels and ingredients of products we take.

CNN.com - Vitamin overload a risk, NIH says - May 18, 2006

No comments:

Related Posts with Thumbnails

Addthis