Should you take a multivitamin or other supplement? 5 questions to ask yourself first.

Taking a multivitamin or other supplements may seem like an easy way to improve your health. But are they actually helpful? And do you really need to take them if your doctor doesn’t suggest adding certain types to your daily routine?

It’s a good question to ask, given that new research is calling into question the benefits of multivitamins. A new cohort study of more than 390,000 U.S. adults without a history of major chronic diseases did not find evidence that healthy adults who regularly take multivitamins live longer. And that’s not the only study to show multivitamins may not protect your health. A 2022 review of more than 80 studies found that taking multivitamins offered “little or no benefit” in preventing cancer, heart disease or death.

Does that mean you should toss your supplements? Maybe not. There are circumstances in which a multivitamin or supplement can help improve your health. To help figure out who might benefit from them and why, here are five questions you can talk over with your health care provider.

Do you eat a balanced diet?

Most people don’t routinely need to take a multivitamin if they eat a diet rich in vegetables, fruit, lean protein like chicken or fish, healthy fats and grains, Dr. Natasha Bhuyan, family physician at One Medical, tells Yahoo Life.

“In fact, it’s better to get nutrients from the food that you eat rather than a vitamin. Plus, the cost of vitamins can add up,” she says.

It’s worth noting that if you’re trying to make up for not eating enough fish by taking fish oil supplements to get those omega-3 fatty acids, you may want to reconsider. That’s because if your heart is healthy, fish oil supplements may actually be harmful. One study found that participants who didn't have a heart condition and took fish oil experienced a 13% increased risk of developing atrial fibrillation, an irregular heartbeat that's linked to heart-related complications. Healthy participants who took fish oil also had a 5% higher risk of having a stroke.

On the other hand, the study found that people who already had heart disease and took fish oil had a 15% lower risk of atrial fibrillation.

Also worth noting: Many people — about 35% of the U.S. population — are deficient in vitamin D, a condition that can be determined with a blood test. While you can get the nutrient from eating a balanced diet that includes foods rich in vitamin D such as salmon, canned tuna and fortified orange juice, along with short bouts in the sun (we’re talking no more than 10 to 15 minutes of sun exposure two to three times a week), talk to your doctor about whether you should take vitamin D supplements.

Are you vegan?

Some people who follow a vegan or vegetarian diet may need to take B vitamins. While it’s possible to get the necessary amounts of B12 — which helps keep blood and nerve cells healthy and helps the body metabolize protein — in some cases a no-meat diet can render others deficient in the vitamin.

“B12 is generally only present in meat, although some grains can be fortified with it,” Dr. Estrelita Dixon, associate professor of internal medicine at UC Health, tells Yahoo Life. “People who are vegan have to educate themselves on ways to get certain vitamins, particularly B12, which is important for blood and nerve health.” Dixon recommends a daily B12 supplement for people who are strict vegans (the recommended daily amount is 2.4 mcg for teens and adults).

Omega-3s are another concern for vegans and vegetarians, says Dr. Patrick Fratellone, cardiologist and integrative medicine doctor in New York. “Since no animal products are consumed, omega-3 must be taken from algae [oil],” he tells Yahoo Life.

Are you immunocompromised or have certain health conditions?

People who have a weak immune system and are not able to eat a balanced diet should take a multivitamin, suggests Fratellone. “Since individuals who are immunocompromised are typically not absorbing nutrients well, the multivitamin should be taken as a liquid,” he says.

Your doctor can order a blood test to determine how much calcium and magnesium you need and whether you’d also benefit from taking certain vitamins such as A, B6, B12, folate, C and D3.

“This is especially important since 40% of the population cannot absorb B12 and folate due to a genetic defect called MTHFR,” Fratellone says. “Those that have this defect … cannot absorb B12 and folate, and have difficulty in detoxifying their bodies.”

Dixon adds that people who have had certain stomach or intestinal surgeries, including gastric bypass, should also check with their doctor about what supplementation they may need, such as vitamin B12, vitamin D and iron.

“Absorption of B12 can also be a problem with medications such as long-term use of [diabetes medication] metformin, so the level should be checked,” she says.

Are you trying to get pregnant?

Women who are trying to conceive should take folic acid daily, says Dixon. Folic acid is found in prenatal vitamins, most multivitamins and in stand-alone supplements. Since nearly half of all pregnancies in the U.S. are unintended, the March of Dimes recommends that all women who can get pregnant should take 400 micrograms of folic acid every day. “This helps reduce the risk of neural tube defects, such as spina bifida, if folic acid is taken in the first eight weeks of pregnancy,” she says.

The March of Dimes recommends that, once pregnant, women should increase that to 600 micrograms of folic acid daily to help with the baby’s growth and development.

When trying to conceive, Fratellone also suggests talking to your doctor to see if you have normal thyroid levels, as well as sufficient iodine, B12 and vitamin D.

Are you going through menopause?

During menopause women experience bone loss, which increases the risk of developing osteoporosis. In fact, up to 20% of bone loss can occur during menopause. Women in this stage of life and who are postmenopausal may benefit from taking vitamin D, as this reduces the risk of bone fracture.

In addition to vitamin D (along with regularly getting in weight-bearing exercises to increase bone mass), Fratellone says women should consider taking the trace mineral boron and calcium for their bones. Talk with your health care provider about how much you should take.

“The recommended amount of calcium for menopausal females has been lowered, as studies have found that higher doses of calcium used in the past put women at risk for heart disease [because] the extra calcium deposited in the heart arteries,” he says.

Bottom line

While it may seem beneficial to add multivitamins and supplements to your diet — and it’s certainly easy to just pick them up at the drug store and start taking them — always consult with your health care provider first.

“There is a lot of information out there about vitamins, and while some of it is accurate, some of it is misinformation,” says Bhuyan. “If you have any questions or concerns about vitamins [and] supplements or other health topics, you can always reach out to your family physician.”