A multivitamin may help provide missing nutrients
Millions of Americans take a daily multivitamin. Health experts agree that certain groups of people can clearly benefit from a multivitamin, especially women who are pregnant or may become pregnant. Others may not need a multivitamin, recent studies show, because the majority of Americans get plenty of nutrients from their daily diet. However, most experts say there is no harm in taking a daily multivitamin and it might help with nutrient balance if, for example, you can't stand eating your veggies, or eat a restricted diet for whatever reason.
There are hundreds of types of multivitamins and there is no standard formula for ingredients because multivitamins are generally targeted to specific nutritional needs, such as gender and age. Multivitamins may be formulated to include nutrients for specific situations such as pregnancy (folic acid) or improved bone health (calcium and D3). Some may have thermogenic ingredients for weight loss (such as niacin, caffeine or green tea extract).
For most healthy adults, taking a daily vitamin will not cause any problems. However, if you have any health concerns, pre-existing conditions, or take other supplements or medications, always check with your health care provider before adding a multivitamin into your regimen. Sometimes the ingredients in multivitamins can interfere with medications you may already take; for example, vitamin K can interfere with blood thinners. Also check with your child's pediatrician before giving your child a multivitamin. We do not cover multivitamins for children because most experts say you should not give your child supplements without a specific recommendation from a health-care provider.
A daily multivitamin is a must for some women
If you are a woman of childbearing age, experts agree you should take a daily multivitamin with at least 400 mcg (micrograms) of folic acid. Folic acid supplements can help prevent neural tube defects, which typically occur very early in pregnancy, often before a woman even knows she's pregnant. This should be a habit whether you intend to become pregnant or not -- better safe than sorry, say experts. Pregnant women need even more folic acid – 600 to 800 mcg.
Some supplements contain folate instead of folic acid. While the terms are used interchangeably by most experts and physicians, and either folate or folic acid is acceptable for supplementation, folate is derived from natural sources, such a broccoli or other foods, while folic acid is the synthetic form. If a supplement contains folic acid, we use that term, if it contains folate, that's how we refer to it. If we're just discussing folic acid levels in general, that is the term we use. While research is ongoing to determine if the human body reacts differently to the two different forms, at this point there have been no conclusions and so take whichever form you prefer unless otherwise directed by your physician.
Are multivitamins safe?
Enacted in 1994, the Dietary Supplement Health and Education Act (DSHEA) restricts the ability of the U.S. Food and Drug Administration (FDA) to regulate supplements or ensure the safety of their ingredients. Under this act, the FDA is limited to collecting information on adverse side effects and to monitoring labeling claims. That means the most the FDA can do is pull a product off store shelves after a problem becomes apparent. It's up to the manufacturer to ensure that its multivitamins and supplements are safe. Under DSHEA, multivitamins don't require FDA approval, and manufacturers aren't required to register their supplements with the FDA before putting them on the market.
In an ideal world, manufacturers would be diligent about the safety of their multivitamins and truth in labeling. However, as professional testing shows, consumers need to be concerned about multivitamin quality. Among 41 products evaluated by ConsumerLab.com, 13 fail at least one test. Many don't meet the nutrient claims on the label, others improperly list ingredients.
It's not unusual for a multivitamin to exceed the upper limit (UL) for niacin and yet stay off of the "not approved" lists of most professional testing organizations. That's because niacin is often targeted to other purposes, such as weight loss or lowering cholesterol. However, it's important to note that niacin can cause flushing and tingling at high doses -- and more serious side effects in a small minority of the population. Again, check with your health care provider if you have any concerns.
Regardless of existing regulations, consumers should be skeptical about health claims listed on multivitamin labels. While the original provisions of DSHEA require that manufacturers make no claims about their products preventing or curing diseases, some do so anyway. Keep in mind, there are no studies to show that any supplement can prevent or cure any condition (with the notable exceptions of iodine and folic acid). The only reason for the average person to take a multivitamin is to ensure you have a full range of daily nutrients, especially if you don't eat a balanced diet.
How to choose the best multivitamin
Choosing a multivitamin can be as difficult as swallowing a horse pill, especially with the multitude of options available. The most important factor in finding the best multivitamin is choosing one that is verified to contain the amount of ingredients that the label claims and that has been tested to be free of contaminants.
Fortunately, several sources provide good coverage of multivitamins to help narrow your choices. ConsumerLab.com is the best reviewer of multivitamins; it tests dozens of products to ensure that they dissolve properly, contain the ingredients listed on the label, and aren't contaminated with lead and other toxins. Some manufacturers pay to have their multivitamins included in the testing through ConsumerLab.com's voluntary Quality Certification Program, but those products are clearly listed in the results table and that payment does not influence the results. ConsumerLab.com's reports are available to subscribers only. Labdoor.com is another good source for laboratory testing of multivitamins. They test a large number of multivitamins for label accuracy, product purity, nutritional value, ingredient safety and projected efficacy. The multis tested are also ranked and rated against one another. Full results are available after free registration. ConsumerReports.org evaluated multivitamins in September 2010 to ensure they meet nutrient claims and dissolve properly, and this is one report that is free to the public; ConsumerReports.org's testing data is generally reserved for subscribers only. Although it's an older report, the products included have not changed so it's still relevant.
User reviews are helpful for information on side effects like stomach upset, any odor or taste issues, and how easy a multivitamin is to swallow. Overall, though, when making our choices we focused our attention on accuracy in labeling to be sure that, when you do make a decision, you get what you're paying for.
Elsewhere in this report:
Multivitamins for Adults over 50 | Multivitamins for Women | Prenatal Multivitamins | Multivitamins for Men | Buying Guide | Our Sources