It’s a supplement jungle out there. Gazillions of vitamin and mineral products loom at you from store shelf and catalog. So how do you find the best without a Ph.D. in nutrition and a spare weekend? Help is here.
Test for the best
Picking a great complete multi is easy — we’ve whittled down more than 25 essential vitamins and minerals to only 9 key nutrients you need to zero in on. Why these 9? They’re the ones our experts say are most likely to come up short in American diets — and to be present in multis in amounts likely to be effective.
Don’t be fooled just because a product calls itself a “multi” or says it’s “complete.” If you check, you may be surprised to find that some multis contain vitamins only or have just a few vitamins and minerals. But the more of the following nine nutrients a multi contains in levels close to our experts’ recommendations, the more complete it is.
This should be the first item you check in a multi, since how much you need differs depending on your age and gender. Find a multi with the iron level you want before you spend time checking other nutrients.
Premenopausal women: Look for up to 18 milligrams, which is 100% of the Daily Value (DV). Adult men and menopausal women: Look for 0 to 9 mg. (0 to 50%DV). (Note: Daily Value is the new name for the old U.S. Recommended Daily Allowance — U.S. RDA — which some labels still use.)
FYI: Premenopausal women having periods lose iron each month and may need the help of a supplement to replace it. But women not having periods and adult men lose little iron normally. And since some research indicates excess iron raises risks of heart disease and colon cancer, many experts now advise men and menopausal women to look for supplements with no or low iron. (Check your breakfast cereal; some are heavily fortified with iron. Take that into account when you select a multi.)
Be aware: Unless you’re diagnosed with iron-deficiency anemia, there’s no reason to take levels above 100% DV.
Look for 5,000 international units (I.U.), which is 100% DV.
FYI: In most multis, the vitamin A is a mix of preformed vitamin A and its precursor, beta-carotene. Not all multis tell you how much comes from each. But even if a multi is all preformed vitamin A or all beta-carotene, 5,000 I.U. is considered a very safe level of each.
Be aware: Don’t supplement above 10,000 I.U. Pregnant women: Don’t go above 5,000 I.U. Too much preformed vitamin A can be toxic or cause birth defects. Can you get too much beta-carotene? Studies show that people with diets high in beta-carotene have lower risks of heart disease and cancer. But in two studies of long-term smokers, those taking high-dose beta-carotene supplements (25 mg or more) developed more lung cancer. Until we know more, a reasonable limit for beta-carotene from supplements (not food) is 6 mg. (That’s what you’d get if 10,000 I.U. of vitamin A were all from beta-carotene.)
Look for 400 I.U. (100% DV).
FYI: Our bodies can manufacture vitamin D from the action of sunlight on the skin, but experts believe many people (especially the elderly and those who routinely use sunblock) may not be exposed to enough sun.
Be aware: Don’t get more than 800 I.U. of vitamin D a day from supplements plus fortified foods on a regular basis. Be sure to count vitamin D from milk (100 I.U. per 8 oz. glass or per 1/3 cup nonfat milk powder) or fortified breakfast cereal (amounts vary).
Look for 2 mg (100% DV).
FYI: American women’s diets appear to be routinely low in B6 (and for some women, oral contraceptives may increase the need). Low intakes are linked to higher levels of heart-attack risk and poorer immune functioning in older people.
Be aware: Don’t overdo B6 (or any other vitamin or mineral, for that matter). Megadoses of 100 mg are associated with (reversible) nerve damage, and problems have been seen at intakes of 50 mg. Reports of high doses of vitamin B6 relieving carpal tunnel syndrome or premenstrual syndrome have not been confirmed by research.
Folic acid (or folate)
Look for 400 micrograms, which is 100% DV. May be listed as 0.4 mg (same as 400 mcg).
FYI: Studies prove that women taking supplements with 400 mcg folic acid prior to and in the first weeks of pregnancy give birth to fewer babies with serious brain and spine defects. There’s strong indication that higher intakes of folic acid may help reduce risks of heart disease (by reducing blood levels of a substance called homocysteine) and colon cancer. But it’s difficult to get 400 mcg in your diet, and most Americans’ diets fall short.
Be aware: The U.S. Public Health Service has urged doctors to tell their patients about the proven and potential benefits of supplements containing 400 mcg folic acid.
Look for 100 mg (25% DV).
That’s the most you’ll find in any single-dose multi supplement (more would make a too-bit-to-swallow pill). In a divided-dose multi, look for up to 400 mg (100% DV) in the day’s total.
FYI: Americans routinely eat far less than 100% DV of this intriguing mineral that’s tentatively linked to protection from diabetes, osteoporosis, atherosclerosis, hypertension and migraine headaches.
Be aware: Excess magnesium can lead to diarrhea. Those with abnormal kidney function would not supplement magnesium without a doctor’s supervision.
Look for 15 mg (100% DV).
FYI: Surveys show this may be the mineral most lacking in Americans’ diets. Zinc is necessary for a strong immune system and proper wound healing.
Be aware: Don’t take supplements with more than 15 mg a day on a regular basis. Too much zinc — in one study, 50 to 75 mg a day — can backfire and lower HDL cholesterol.
Look for 2 mg (100% DV).
FYI: Here’s another mineral the average diet runs low on. Copper plays a role in bone and heart health, blood-sugar regulation and iron use.
Be aware: If your supplement has zinc, make sure it has copper, too. Elevating zinc intake without taking in enough copper can suppress copper absorption.
Look for 50 to 200 mcg., a safe and adequate range set by the National Research Council.
FYI: Research indicates it may be difficult to get even the minimum amount of chromium we need from food. This important mineral helps the body handle blood sugar; low levels of chromium may increase our risk of adult-onset diabetes.
Note: You may not see a % DV for chromium; instead, there may be an asterisk (*) that indicates “Daily Value not established.” That was the case until 1996, when the Food and Drug Administration set a DV for chromium of 120 mcg; it may take time for labels on some brands of supplements to catch up.
Be aware: Does extra chromium help with weight loss or building muscle? Most studies so far don’t bear this out.
What if other vitamins and minerals are present in a multi? Consider them nice-to-have but not necessary. For vitamins C and E and calcium, keep on reading. For most of the others, it’s preferable if levels stay in the 100%-DV-or-lower range. (Exception: People over the age of 60 may want to take extra vitamin B12 — from 200% to 500% DV — to make up for problems they may have in absorbing vitamin B12 from food.)
Wondering why we omitted three super-important nutrients — vitamin C, vitamin E and calcium — from the nine nutrients to look for in a multi? Because we think there’s good reason to consider taking each one as a single supplement — in amounts you won’t find the standard singe-dose multi supplement.
Consider taking 200 to 500 mg of this antioxidant vitamin as a single supplement. Otherwise, make sure your multi has at least 60 mg (100% DV).
Evidence: A study at the National Institutes of Health found that we need 200 mg of vitamin C to keep blood plasma at 85% saturation level. For 95% saturation, we need 400 to 500 mg (Proceedings of the National Academy of Science, April 1996). Researchers concluded that the current DV of 60 mg may be too low.
People with diets high in vitamin C have lower rates of cancer and heart disease. Although we are far from having proof, some studies hint that vitamin C supplements may help lower risk of cataracts, as well as help people with diabetes.
Look for: Vitamin C supplements in 100, 250 or 500 mg tablets. Or find chewable tablets (to protect tooth enamel, chew only one a day) or effervescent tablets or powder that dissolve in water. You may find 100 mg or more of vitamin C in some multis.
Natural vs. synthetic: Your body doesn’t know the difference between vitamin C from rose hips or a laboratory. There’s no evidence so far that we need vitamin C in a buffered form called ester-C.
Best way to take: Divide your dose in two; take half in the morning, half at night. Reason: After 12 hours, your body returns to presaturation levels, no matter what amount of vitamin C you’ve taken.
Can you get 200 to 500 mg from food? It’s possible if you eat lots of vitamin-C-rich fruits and vegetables. An 8-oz. glass of orange juice from concentrate, for example, has 100 mg. A cup of fresh strawberries has 85 mg. One-half cup frozen broccoli cooked has 40 mg.
Be aware: Although 1,000 mg of vitamin C yielded 100% saturation of blood plasma in the NIH study, some research (but not all) suggests taking that much vitamin C may increase risk of kidney stones. Diarrhea may occur at intakes of several thousand mg.
Consider taking 100 to 400 I.U. of this antioxidant vitamin.
Most multis supply only about 30 I.U. (100% DV), much less than the levels some research indicates may fight illness, especially heart disease. If you don’t take extra vitamin E, make sure your multi has at least 30 I.U.
Evidence: Among the best indication that extra E may help is a British study of over 2,000 men and women with narrowed coronary arteries. Participants took either 400 or 800 I.U. of E, or a placebo. The result: After 18 months, E takers (of either dose) lowered chances of getting a nonfatal heart attack by 75% (Lancet, March 23, 1996). Other research suggests (but doesn’t prove) extra E might reduce risks of cataracts and some cancers and help people with diabetes.
Look for: Vitamin E supplements in 100, 200 or 400 I.U. capsules. Also available in chewable or liquid form.
Natural vs. synthetic: Though natural vitamin E is more bioactive in the body than synthetic E, the difference in potency is taken into account in the International Unit. That means 100 I.U. of synthetic vitamin E is as potent as 100 I.U. of natural E. Most research, by the way, uses synthetic. To know which type your supplement has, read the list of ingredients. Natural E is d-alpha tocopherol; synthetic is d,l-alpha tocopherol or d,l-alpha tocopheryl acetate.
Best way to take: With a meal that contains at least a little fat, to help with absorption.
Can you get 100 to 400 I.U. vitamin E from food? Hardly! You’d need 2 cups of corn oil, one of the best source to get 100 I.U.
Be aware: If you’re on blood-thinning medication or at risk for uncontrolled bleeding, talk with your doctor before taking vitamin E at these levels.
Depending on the calcium in your diet, consider single supplements containing about 500 to 1,000 mg of this crucial bone protector.
Evidence: It surprises many people that singe-dose multi supplements are never “complete” with 100% DV for calcium (1,000 mg). In fact, that would be impossible — all that calcium would make a single tablet too big to swallow. Some single-dose multis do have about 200 mg. But since surveys show many diets lag well behind recommended daily levels, a separate calcium supplement is worth considering.
Supplements made simple
So that’s it — the quickest way to find a great multi by looking for nine key nutrients. Plus three nutrients to consider taking as singles. You’ll be an instant expert next time you cruise that supplement aisle.