Quick answer

One serving a day, as the label directs: a single pill for most basic multis, two or more for some products. Basic multis keep most nutrients at or below 100% of the Daily Value. Taking more is not better, because each nutrient has its own adult upper limit, such as 35 mg of niacin from supplements.^1,2

Key facts

The Daily Value is often close to the RDA, the amount that meets the needs of 97 to 98% of healthy people.^1,3
High-potency products can go above the upper limit for some nutrients.¹
In one large study, 48 to 61% of multi users had excessive intakes of niacin.¹
There is no single milligram figure for a multivitamin: each nutrient has its own amount and its own limit.⁴

One serving, as the label says

Basic multis are taken once a day and contain all or most vitamins and minerals, most of them in amounts that do not exceed the Daily Value or the recommended intake.^1,3

High-potency products contain some vitamins or minerals well above the Daily Value, in some cases above the upper limit, and may come as two or more pills to take each day.^1,3

A serving is whatever the Supplement Facts panel lists as the serving size. If that says two capsules, the amounts printed are for both together, and two capsules is the whole day's dose rather than a double one.

Asking how many milligrams a multivitamin is has no single answer. A multi is twenty or so separate amounts, from a few micrograms of vitamin B12 to hundreds of milligrams of calcium in some products, and each one is judged against its own need and its own limit.^4,5

What the % Daily Value tells you

Labels show each nutrient as a percentage of its Daily Value (DV). The DV is often, but not always, close to the Recommended Dietary Allowance, the daily amount that covers the needs of nearly all (97 to 98%) healthy people.^1,3

The Daily Value is one number for all adults, while real needs vary by age and sex. Iron shows the gap most clearly: its Daily Value of 18 mg is what women aged 19 to 50 need, but men and everyone over 50 need 8 mg.⁶

A percentage above 100 is not a mark of quality. The question to ask is whether any nutrient, once your food and other supplements are added, goes past its upper limit.³

Upper limits that apply to a multi

Adult upper limits for nutrients often found in multis^{2,4,5,6,7,8,9}
Nutrient	Adult upper limit a day
Niacin	35 mg, from supplements
Folic acid	1,000 mcg, from supplements and fortified foods
Magnesium	350 mg, from supplements and medicines
Vitamin A, preformed (retinol)	3,000 mcg; no limit for beta-carotene
Vitamin D	100 mcg (4,000 IU)
Vitamin B6	100 mg
Zinc	40 mg
Iron	45 mg
Calcium	2,500 mg to age 50, then 2,000 mg
Selenium	400 mcg
Copper	10 mg

The limits for vitamin A, vitamin D, iron and calcium count food, drinks and supplements together. Niacin, folic acid and magnesium are the exceptions in the table, where only the added forms count.^{2,4,5,6,7,8,9}

The nutrients most likely to run over are the five NIH names for multis: iron, vitamin A, zinc, niacin and folic acid.³

Add up every source

In a study of 90,771 adults aged 45 and older, 10 to 15% of multi users had excessive intakes of vitamin A, iron or zinc, and 48 to 61% had excessive intakes of niacin.¹

That study counted food and multis only. NIH says going over is even more likely when people also take single vitamin or mineral supplements, or eat fortified foods such as breakfast cereals.^1,3

List every supplement you take, including single vitamins, calcium or vitamin D tablets, and protein or electrolyte powders
Check fortified foods and drinks, such as breakfast cereals, for added vitamins and minerals³
Add up iron, vitamin A, zinc, niacin and folic acid first, and compare the totals with the table above³

What's in ours

What’s in ours

Men's Multi: Vitamin A, 600 mcg RAE per serving, from the label

Our Men's Multi's serving is two capsules, taken once a day with a meal. The amounts on its label are for both capsules together.

Children and pregnancy

Most children's multis provide nutrients in smaller amounts that suit children.³

Accidental swallowing of iron supplements caused about a third of the poisoning deaths in US children reported from 1983 to 1991. Keep any product that contains iron out of children's reach.⁶

Too much preformed vitamin A (retinol) during pregnancy can cause birth defects. Beta-carotene does not carry this risk, and prenatal multis generally leave retinol out.^1,3,8

Adult doses are not for children. If you are pregnant or could become pregnant, ask your doctor which multi to take, because a prenatal formula is built for those needs.³

Questions people ask

Can I take two multivitamins a day?

Only if the label's serving is two pills. Doubling a once-a-day multi doubles every nutrient, and for iron, vitamin A, zinc, niacin and folic acid that can mean going over the upper limit, especially if your diet includes fortified foods.³

How many mg is a multivitamin?

There is no single figure. Each nutrient has its own amount, in milligrams or micrograms, and its own upper limit. Compare the label line by line rather than the size of the pill.⁴

Is the dose different for women?

It is still one serving a day. What changes is the formula: women aged 19 to 50 need 18 mg of iron a day, and women who could become pregnant should get 400 mcg of folic acid.^6,7

See what we make

Every product shows its whole label and what its lab report covers. The store opens soon.

See the Full Measure line Men's Multi

Sources

This page is information, not medical advice. Talk to your doctor or pharmacist about your own situation.