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Fortify Your Knowledge About Vitamins

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Vitamins are essential nutrients that contribute to a healthy life. Although most people get all the vitamins they need from the foods they eat, millions of people worldwide take supplemental vitamins as part of their health regimen.

Why Buy Vitamins?

There are many good reasons to consider taking vitamin supplements, such as over-the-counter multivitamins. According to the American Academy of Family Physicians (AAFP), a doctor may recommend that you take them:

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Vitamin Facts

Your body uses vitamins for a variety of biological processes, including growth, digestion, and nerve function. There are 13 vitamins that the body absolutely needs: vitamins A, C, D, E, K, and the B vitamins (thiamine, riboflavin, niacin, pantothenic acid, biotin, vitamin B-6, vitamin B-12 and folate). AAFP cites two categories of vitamins.

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Practice Safety with Dietary Supplements

When it comes to purchasing dietary supplements, Vasilios Frankos, Ph.D., Director of FDA's Division of Dietary Supplement Programs, offers this advice: "Be savvy!"

Today's dietary supplements are not only vitamins and minerals. "They also include other less familiar substances such as herbals, botanicals, amino acids, and enzymes," Frankos says. "Check with your health care providers before combining or substituting them with other foods or medicines." Frankos adds, "Do not self-diagnose any health condition. Work with your health care providers to determine how best to achieve optimal health."

Consider the following tips before buying a dietary supplement:

Other red flags include claims about limited availability, offers of "no-risk, money-back guarantees," and requirements for advance payment.

"Also ask yourself, "Is the product worth the money?'" Frankos advises. "Resist the pressure to buy a product or treatment on the spot. Some supplement products may be expensive or may not provide the benefit you expect. For example, excessive amounts of water-soluble vitamins, like vitamins C and B, are not used by the body and are eliminated in the urine."

Develop a Vitamin Strategy

It is important for consumers to have an overall strategy for how they will achieve adequate vitamin intakes. The 2005 Dietary Guidelines for Americans advises that nutrient needs be met primarily through consuming foods, with supplementation suggested for certain sensitive populations.

These guidelines, published by the Department of Health and Human Services and the U.S. Department of Agriculture (USDA), provide science-based advice to promote health and to reduce risk for chronic diseases through diet and physical activity. They form the basis for federal food, nutrition education, and information programs.

Barbara Schneeman, Ph.D., Director of FDA's Office of Nutritional Products, Labeling, and Dietary Supplements, says, "The Guidelines emphasize that supplements may be useful when they fill a specific identified nutrient gap that cannot or is not otherwise being met by the individual's intake of food." She adds, "An important point made in the guidelines is that nutrient supplements are not a substitute for a healthful diet."

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Special Nutrient Needs

According to the Dietary Guidelines for Americans, many people consume more calories than they need without taking in recommended amounts of a number of nutrients. The Guidelines warn that there are numerous nutrients—including vitamins—for which low dietary intake may be a cause of concern. These nutrients are:

Regarding the use of vitamin supplements, the Dietary guidelines include the following:

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How Vitamins are Regulated

Vitamin products are regulated by FDA as "Dietary Supplements." The law defines dietary supplements, in part, as products taken by mouth that contain a "dietary ingredient" intended to supplement the diet.

Listed in the "dietary ingredient" category are not only vitamins, but minerals, botanicals products, amino acids, and substances such as enzymes, microbial probiotics, and metabolites. Dietary supplements can also be extracts or concentrates, and may be found in many forms. The Dietary Supplement Health and Education Act of 1994 requires that all such products be labeled as dietary supplements.

In June 2007, FDA established dietary supplement "current Good Manufacturing Practice" (cGMP) regulations requiring that manufacturers evaluate their products through testing identity, purity, strength, and composition.

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Risks of Overdoing It

As is the case with all dietary supplements, the decision to use supplemental vitamins should not be taken lightly, says Vasilios Frankos, Ph.D., Director of FDA's Division of Dietary Supplement Programs.

"Vitamins are not dangerous unless you get too much of them," he says. "More is not necessarily better with supplements, especially if you take fat-soluble vitamins.” For some vitamins and minerals, the National Academy of Sciences has established upper limits of intake (ULs) that it recommends not be exceeded during any given day. (For more information, visit www.nap.edu/catalog.php?record_id=6432#toc

Also, the AAFP lists the following side effects that are sometimes associated with taking too much of a vitamin.

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Fat-soluble Vitamins

If you take blood thinners, talk to your doctor before taking vitamin E or vitamin K pills.

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Water-soluble Vitamins

Taking too much of a vitamin can also cause problems with some medical tests or interfere with how some drugs work.

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Report Problems

If you believe that you are experiencing an adverse response to taking a vitamin or any dietary supplement, Frankos advises reporting it to your health care provider, as well as to the manufacturer whose name or phone number appears on the label. You can also report directly to FDA through its MedWatch program at 1-800-FDA-1088 or online at www.fda.gov/medwatch

Starting December 22, 2007, any serious adverse events reported to a dietary supplement manufacturer must be reported to FDA within 15 days of the manufacturer receiving the adverse event report.

This article appears on FDA's Consumer Health Information Web page (www.fda.gov/consumer), which features the latest updates on FDA-regulated products. Sign up for free e-mail subscriptions at www.fda.gov/consumer/consumerenews.html.

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For More Information

FDA 101: Dietary Supplements
http://www.fda.gov/consumer/updates/supplements080408.html

Dietary Supplements
www.cfsan.fda.gov/~dms/supplmnt.html

What Dietary Supplements Are You Taking?
www.cfsan.fda.gov/~dms/ds-take.html

Dietary Guidelines for Americans, 2005
www.health.gov/dietaryguidelines/dga2005/document/default.htm

National Institutes of Health Office of Dietary Supplements
http://dietary-supplements.info.nih.gov/

Dietary Reference Intakes: A Risk Assessment Model for Establishing Upper Intake Levels for Nutrients
www.nap.edu/catalog.php?record_id=6432

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Date Posted: November 19, 2007
Updated: November 21, 2007

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