What to Know Before Choosing a Multivitamin

Walk down any supplement aisle and you will find dozens of multivitamins: for men, women, seniors, energy, immunity and more. Since no rule fixes what a multivitamin must contain, the differences are real. These eight checks will help you choose a product that fits your needs.

1. Start with your diet

A multivitamin fills gaps; it does not fix a poor diet. Think about what you regularly eat. If you avoid dairy, for example, calcium and vitamin D may be your priorities. If you are vegan, vitamin B12 matters most.

2. Match the formula to your life stage

• Women of childbearing age: products usually include more iron and 400 micrograms of folic acid. See Women’s Multivitamin with Iron.
• Men: formulas typically contain little or no iron. See Men’s Daily Multivitamin.
• Adults over 50: often less iron and more vitamin D and B12.
• Pregnancy: a prenatal product chosen with your healthcare provider.
• Children: only products made for their age group.

3. Check the percent Daily Value

The %DV column shows how each nutrient compares with daily reference amounts. For a general multivitamin, amounts near 100% DV are sensible. Very high percentages are rarely needed and increase the risk of exceeding upper limits when combined with food and other supplements.

Calcium and magnesium are bulky, so most multivitamins contain well below 100% DV of these.

4. Look at the iron content

Iron needs differ widely. The NIH advises that adult men and postmenopausal women should generally avoid multivitamins with 18 mg or more of iron unless a doctor has recommended it. Iron-containing supplements are a leading cause of poisoning in young children, so store them out of reach.

5. Check vitamin A and beta-carotene

High intakes of preformed vitamin A (retinol) in pregnancy increase the risk of birth defects. People who smoke or used to smoke should avoid supplements with large amounts of beta-carotene or vitamin A, which have been linked to a higher risk of lung cancer in smokers.

6. Consider your medicines

Vitamin K can reduce the effect of the blood thinner warfarin. Minerals such as calcium and iron can interfere with the absorption of some antibiotics and thyroid medication. Ask your pharmacist how to time them.

7. Check the form and the other ingredients

Tablets, capsules, softgels, chewables and gummies all work; choose one you will take regularly. Gummies often contain added sugar and fewer minerals. Read the “other ingredients” for gelatin, allergens and colorings if these matter to you.

8. Consider quality signals

Look for a clear Supplement Facts panel, the manufacturer’s contact details, a lot number and an expiration date. Independent quality seals indicate that a product has been tested for content and contaminants.

Avoid doubling up

If you already take single supplements, such as vitamin D or calcium, add up the totals. Fortified cereals, drinks and bars count as well.

How to take it

Take your multivitamin with food and at a consistent time of day. Do not take more than the label recommends. Our Daily Multivitamin is taken once a day with a meal.

When to ask first

Speak to a doctor or pharmacist before starting if you are pregnant, breastfeeding, taking prescription medicine, managing a long-term condition or preparing for surgery.

The bottom line

The best multivitamin is a moderate one that suits your age, sex and diet, taken as directed. More is not better. Compare formulas in our vitamins and nutrition range.

Sources

1. NIH Office of Dietary Supplements. Multivitamin/mineral Supplements.
2. U.S. Food and Drug Administration. Daily Value on the Nutrition and Supplement Facts Labels.
3. U.S. Food and Drug Administration. Information for Consumers on Using Dietary Supplements.
4. U.S. Food and Drug Administration. Mixing Medications and Dietary Supplements Can Endanger Your Health.