Today's Health Tips
A recent government study said more than half of all Americans take
dietary supplements, which in my opinion is surprisingly high,
considering these pills and powders aren't regulated like drugs but like
foods.
The Dietary Supplement Health and Education Act (DSHEA) of 1994
defined "dietary supplement" (to include vitamins, minerals, botanicals
and other ingredients) and ruled that supplements would be regulated
like foods. This exempted companies from having to prove the safety or
efficacy of their products-entirely reasonable, given that the nutrients
come from natural foods, say advocates. The law also permitted
supplement makers to use several kinds of marketing claims (some that
don't require FDA approval), including structure/function statements,
which describe how a nutrient is intended to affect the body.
Allowing such claims-without requiring proof of strong science to back
them-is why there's so little conclusive science on supplements, say
the law's critics. "The marketing has been quite effective without
studies," says Irwin Rosenberg, M.D., senior scientist and interim
director of the Neuroscience and Aging Laboratory at the Jean Mayer USDA
Human Nutrition Research Center on Aging at Tufts University. Even some
in the supplement industry warn that lax marketing can be misleading.
"There are a few real egregious folks who go over the line with loose
structure/function claims," says Andrew Shao, Ph.D., Vice President,
Global Product Science & Safety at Herbalife. "Unfortunately
consumers get the message, 'all supplement makers are out to dupe me.'"
What do the claims really mean? The answers may surprise you. Here are 5
myths about vitamins busted, originally reported on in EatingWell
Magazine by Nicci Micco.
Myth 1: All "Multivitamins" Are the Same
The Truth: There's no legal definition for "multivitamin."
Manufacturers apply the term to any product supplying two or more
vitamins (minerals, phytochemicals and herbs too). In a 2006 study of
26,735 people out of the University of Hawaii in Honolulu, the
"multivitamins" subjects reported using included 1,246 different
formulas. Nearly 70 percent were "one-a-day" types; 16 percent,
B-complex blends; and 14 percent, "antioxidant" mixes. Products in the
same group (e.g., B-complex) varied wildly; many provided megadoses of
some nutrients.
The Bottom Line: Read labels to find a "multi" that doesn't exceed 100 percent of the Daily Value (DV) for any nutrients.
Myth 2: What's Listed on the Label Is What's Really in the Product
The Truth: Supplement manufacturers must list each ingredient (and its
quantity) in a product, but they don't have to prove the accuracy of
these lists. Limited in resources, the FDA doesn't check that what's
inside a product jibes with what's on its label, either. Often labels
don't match contents: 30 percent of "multivitamins" tested by
ConsumerLab.com, an independent nutrition product testing service and
consumer watchdog group, were "off" for at least one ingredient, says
Tod Cooperman, M.D., the group's president. Some delivered doses well
below those listed on the label; one was tainted with potentially
dangerous levels of lead.
Manufacturers can pay to have products tested by ConsumerLab.com or a
similar independent company, U.S. Pharmacopeia (USP), usp.org, to verify
that the formula: 1) is what it's supposed to be, 2) doesn't contain
contaminants, and 3) dissolves properly in the body. (Note: Such
certification doesn't guarantee safety or effectiveness, just that a
product is what the label says.) "Passing" products earn the right to
bear a special seal. The absence of a seal doesn't necessarily signal a
bad product: big companies often do their own quality-assurance testing.
The Bottom Line: Buy products with a certified seal-such as the USP seal or certification from ConsumerLab.com-or an established brand.
Myth 3: Calcium Is Calcium
The Truth: Vitamins and minerals occur in different forms-all of which may not function equally. A 2005 study in the Journal of the American Dietetic Association
showed that an orange juice fortified with calcium citrate malate was
absorbed 48 percent better than one fortified with the same amount of
calcium in a different form. Manufacturers don't have to prove that
nutrients they add to foods are actually absorbed.
Bottom line: A dietitian can help you pick products likely to be well absorbed.
Myth 4: Structure/Function Claims Are Backed By Solid Science
The Truth: Structure/function claims (e.g., "Zinc helps maintain
immunity") describe what an ingredient is intended to do in the body.
Often, the research behind the claim has no scientific consensus. (Look
closely: packages with structure/function claims must also bear the
disclaimer, "This statement has not been evaluated by the Food and Drug
Administration. This product is not intended to diagnose, treat, cure or
prevent any disease.") "Claim-featured" nutrients sometimes are
included purely for marketing.
Example: Research on phytochemicals (such as lycopene) is still new
and their potential benefits poorly understood. Yet "manufacturers will
throw in just a tiny bit," says Cooperman. "If consumers have heard of
an ingredient, they assume it has some value." "Premium" ingredients can
mean the difference between charging $50, versus $8, for a bottle of
multivitamins.
The Bottom Line: Watch out for "buzz word" nutrients and claims that appear too good to be true.
Myth 5: "Studies Have Shown…" Means That Clinical Research Conclusively Showed Whatever Statement Follows
The Truth: Most studies that "show" a vitamin/mineral supplement
provides a health benefit are observational ones, which survey people
about various behaviors (e.g., diet, exercise, supplement use), then use
statistical analyses to identify links with disease. When an
observational research finds, "People who took a multivitamin, daily,
for 'X' number of years have an 'X' percent lower chance of developing
colon cancer than those who didn't," one can't assume that the
multivitamin (not a combination of factors) was fully responsible.
Surveys show that supplement users tend to practice other healthy
habits, too-eating lots of vegetables, shunning cigarettes and
exercising regularly-so it's hard to tease out a single protective
factor.
This is why diet/disease links found in observational studies must be
confirmed in controlled randomized clinical trials. In these
"gold-standard" investigations, researchers deliver specific nutrient
doses to one group and placebo "sugar supplements" to another (neither
the subjects nor the investigators know who's getting what) to test
whether a supplement is really responsible for observed benefits.
The Bottom Line: Supplement makers don't have to say how scientifically conclusive their studies are.
Do you take a dietary supplement?
Brierley's interest in nutrition and food come together in her position as nutrition editor at EatingWell.
Brierley holds a master's degree in Nutrition Communication from the
Friedman School of Nutrition Science and Policy at Tufts University. A
Registered Dietitian, she completed her undergraduate degree at the
University of Vermont.
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