Is There Really Any Benefit to Multivitamins?
A recent look at
multivitamins by Johns Hopkins researchers shows that there’s no proof of
benefit, but there is evidence of possible harm from high doses of certain
vitamin supplements. Find out the one supplement deemed beneficial—and how
others failed
WHAT THE EXPERTS DO
Healthy Food Instead of Supplements
“I don’t take any supplements routinely,” says Larry Appel,
M.D., director of the Johns Hopkins Welch Center for Prevention, Epidemiology
and Clinical Research. “I try to eat three healthy meals a day to get the
vitamins, minerals and other nutrients I need.” How he does it:
Plenty of produce. “I aim for two or more servings of fruits or vegetables at every meal,” he says. “I enjoy salads and have one for lunch or dinner several times a week.”
Low-fat dairy and whole grains. “Low-fat or fat-free milk and yogurt provide calcium, magnesium, potassium and other nutrients,” he says. “I have cereal with milk for breakfast a few times a week. And I have yogurt sometimes too.”
Protein. “At home we usually have fish or chicken for dinner. I am not a vegetarian; rather, I eat minimal meat,” Appel says. Some fish, such as salmon, are a good source of healthful omega-3 fatty acids.
Plenty of produce. “I aim for two or more servings of fruits or vegetables at every meal,” he says. “I enjoy salads and have one for lunch or dinner several times a week.”
Low-fat dairy and whole grains. “Low-fat or fat-free milk and yogurt provide calcium, magnesium, potassium and other nutrients,” he says. “I have cereal with milk for breakfast a few times a week. And I have yogurt sometimes too.”
Protein. “At home we usually have fish or chicken for dinner. I am not a vegetarian; rather, I eat minimal meat,” Appel says. Some fish, such as salmon, are a good source of healthful omega-3 fatty acids.
Half of all American adults—including 70 percent of those age 65
and older—take a multivitamin or another vitamin or mineral supplement
regularly. The total price tag exceeds $12 billion per year—money that Johns
Hopkins nutrition experts say might be better spent on nutrient-packed foods
like fruit, vegetables, whole grains and
low-fat dairy products.
In an editorial in
the journal Annals of Internal Medicine titled “Enough Is Enough: Stop Wasting
Money on Vitamin and Mineral Supplements,” Johns Hopkins researchers reviewed
evidence about supplements, including three very recent studies:
·
An analysis of research involving 450,000 people, which found
that multivitamins did not reduce risk
for heart disease or cancer.
·
A study that tracked the mental functioning and multivitamin use
of 5,947 men for 12 years found that multivitamins did
not reduce risk for mental declinessuch as memory loss or slowed-down
thinking.
·
A study of 1,708 heart attack survivors who took a high-dose
multivitamin or placebo for up to 55 months. Rates of later heart attacks, heart surgeries and deaths were
similar in the two groups.
The Vitamin Verdict
The researchers concluded that multivitamins don’t reduce the
risk for heart disease, cancer, cognitive decline (such as memory loss and
slowed-down thinking) or an early death. They also noted that in prior studies,
vitamin E and beta-carotene supplements appear to be harmful, especially at
high doses.
“Pills are not a shortcut to better health and the prevention of chronic diseases,” says Larry Appel, M.D., director of the Johns Hopkins Welch Center for Prevention, Epidemiology and Clinical Research. “Other nutrition recommendations have much stronger evidence of benefits—eating a healthy diet, maintaining a healthy weight, and reducing the amount of saturated fat, trans fat, sodium and sugar you eat.”
The exception is supplemental folic acid for women of child-bearing potential, Appel says. “Folic acid prevents neural tube defects in babies when women take it before and during early pregnancy. That’s why multivitamins are recommended for young women.” The Centers for Disease Control and Prevention recommends that all women of reproductive age get 400 micrograms of folic acid daily. The amount of iron in a multivitamin may also be beneficial for women of child-bearing potential, Appel adds.
“I don’t recommend other supplements,” Appel says. “If you follow a healthy diet, you can get all of the vitamins and minerals you need from food.”
“Pills are not a shortcut to better health and the prevention of chronic diseases,” says Larry Appel, M.D., director of the Johns Hopkins Welch Center for Prevention, Epidemiology and Clinical Research. “Other nutrition recommendations have much stronger evidence of benefits—eating a healthy diet, maintaining a healthy weight, and reducing the amount of saturated fat, trans fat, sodium and sugar you eat.”
The exception is supplemental folic acid for women of child-bearing potential, Appel says. “Folic acid prevents neural tube defects in babies when women take it before and during early pregnancy. That’s why multivitamins are recommended for young women.” The Centers for Disease Control and Prevention recommends that all women of reproductive age get 400 micrograms of folic acid daily. The amount of iron in a multivitamin may also be beneficial for women of child-bearing potential, Appel adds.
“I don’t recommend other supplements,” Appel says. “If you follow a healthy diet, you can get all of the vitamins and minerals you need from food.”
Whole grains: Grains such
as whole wheat, brown rice and barley still have their fiber-rich outer shell,
called the bran, and inner germ. It provides vitamins, minerals and good fats.
Choosing whole grain side dishes, cereals, breads and more may lower the risk
for heart disease, type 2 diabetes and cancer and improve digestion, too.
Saturated fat: A type of fat
found in abundance in butter, whole milk, ice cream, full-fat cheese, fatty
meats, poultry skin, and palm and coconut oils. Saturated fat raises levels of
heart-threatening LDL cholesterol in your bloodstream. It can also interfere
with your body’s ability to absorb blood sugar easily. Limiting saturated fat
can help control your risk for heart disease.
Omega-3 fatty acids (oh-may-ga
three fah-tee a-sids): Healthy polyunsaturated fats that the body uses to build
brain-cell membranes. They’re considered essential fats because our body needs
them but can’t make them on its own; we must take them in through food or
supplements. A diet rich in omega-3s—found in fatty fish, like salmon, tuna and
mackerel, as well as in walnuts, flaxseed and canola oil—and low in saturated
fats may help protect against heart disease, stroke, cancer and inflammatory
bowel disease.
Do multivitamins make you healthier?
Some experts say it's time to give up on daily multivitamins to preserve health, but others disagree. What should you do?
If you take a multivitamin, it's probably because you want to do everything you can to protect your health. But there is still limited evidence that a daily cocktail of essential vitamins and minerals actually delivers what you expect. The latest round of studies, published in December in Annals of Internal Medicine, found no benefit from multivitamins in protecting the brain or heart. But some Harvard experts think there is still hope.
"There are potential benefits and there are no known risks at this time," says Dr. Howard Sesso, an associate professor of epidemiology at the Harvard School of Public Health. "It is worth considering a multivitamin as part of a healthy lifestyle."
In contrast, an editorial published alongside the multivitamin studies urged consumers to "stop wasting money on vitamin and mineral supplements."
Caught between expert opinions, what do you do? Start with asking yourself why you would consider taking a multivitamin. If you suspect your diet is nutritionally lax, focus your efforts there.
What we know so far
Despite all the research on vitamins and health, we have only a handful of rigorous scientific studies on the benefits of what Dr. Sesso calls a "true" multivitamin: a pill that provides essential vitamins and minerals at the relatively low levels that the body normally requires.
The Physicians' Health Study II is the best study completed so far. It was the first and only large-scale randomized clinical trial to test a commonly taken multivitamin like the ones most people take, containing the daily requirements of 31 vitamins and minerals essential for good health.
A large group of male physicians took either a multivitamin or a placebo pill for more than a decade. The results have been mixed, with modest reductions in cancer and cataracts, but no protective effect against cardiovascular disease or declining mental function. Is it safe?
Multivitamin advocates point to the lack of any strong proof that taking a multivitamin for many years is dangerous. But Dr. Eliseo Guallar, one of those who panned multivitamins in the Annals editorial, emphasizes that lack of evidence that multivitamins are harmful doesn't mean they're safe. We simply don't know.
"While I agree that the likelihood of harm is small, the likelihood of a clear health benefit is also very small—and also we have no clear proof yet of such benefit," says Dr. Guallar, a scientist at the Johns Hopkins Bloomberg School of Public Health.
Dr. Sesso speaks for the optimists, who urge a wait-and-see approach. "Multivitamin supplementation is low risk and low cost, and it helps to fill potential gaps in the diet that people might have," Dr. Sesso says. "These are compelling reasons to consider taking a multivitamin for cancer and eye disease that should be discussed with your physician."
For now, you can take certain steps:
- Ask your doctor if you really need to take a multivitamin. Could you have a vitamin deficiency?
- Assess your diet. Do you eat as healthy as you could? Is anything lacking?
- Do you want expert nutritional advice? See a dietician. Also, Medicare beneficiaries get an annual "wellness" visit with their primary care providers.
Do not take high doses of specific vitamins, especially A and E. These may actually be harmful. Some research suggests that generous daily doses of vitamin D could be helpful.
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