Do Multivitamins Actually Work?

People opt to take multivitamins for various reasons, including helping the body avoid nutritional gaps, support certain health outcomes, or boost energy levels. But multivitamins are supplements, and with any supplement or new medication you take, it's important to ask questions about how it will actually benefit you. As a dietitian, when people ask me "do multivitamins work?", my answer is an annoying "it depends".

Multivitamins are supplements that contain many different vitamins and minerals, often along with other ingredients. They're available in many forms, such as tablets, capsules, chewable gummies, powders, and liquids, and approximately one-third of all adults in the United States take one.

But whether you (or your family) should take a multivitamin depends on a variety of factors, from diet to medical history. Ahead, all your multivitamin questions answered including, do multivitamins work and whether or not you should take them.

Melissa Mitri, MS, RD, is a registered dietitian and nutrition writer.

For some people, yes, multivitamins work.

What you eat and drink fuels your body with the nutrients necessary to allow the body to function properly. In a perfect world, most people would eat enough nutrient-dense foods like produce, beans, nuts, and legumes to provide the body with all the nutrients it needs in adequate amounts. Unfortunately, however, most Americans are missing the mark when it comes to eating the right balance of foods. For example, the CDC suggests that only 10% of adult Americans eat the recommended servings of fruits and vegetables every day.

And that is where multivitamins come into play. Multivitamins are a supplement that contains many vitamins. "They're great because you can get various essential nutrients in one vitamin instead of taking the nutrients individually," Melissa Mitri, MS, RD, registered dietitian and nutrition writer, told POPSUGAR. Some multivitamins many also contain minerals, herbs, or other additions.

Taking a multivitamin can provide the body with nutrients it may not be receiving via your diet, especially if you are not eating enough of certain food groups (or you are completely eliminating certain foods). Theoretically, taking a multivitamin will ensure your body receives enough of these micronutrients, even if your diet is falling short. But every body is different and what works for one person may not work for you.

Intuitively, it makes sense to believe that taking a multivitamin is a simple step to ensure you don't experience nutrition gaps. But when you look closely at the medical literature, the argument of whether everyone would benefit from one is mixed.

Recent data published in Alzheimer's & Dementia showed that older adults who took the daily multivitamin supplement Centrum Silver had improved cognition and memory. And other data shows that there may be eye health benefits when taking certain multivitamins. For pregnant people specifically, a prenatal vitamin that contains certain minerals can significantly reduce a wide range of pregnancy complications (like anemia and gestational diabetes).

"Science-backed benefits of taking a multivitamin include enhanced immune function, improved mental health, and better energy levels," Mitri shared. She also added that "specific populations may benefit more from multivitamins, including vegetarians and vegans, who are missing critical nutrients in their diet."

Taking multivitamins doesn't come without risks and may not be for everyone.

According to an analysis in the journal Annals of Internal Medicine, after analyzing research involving 450,000 people, researchers found that multivitamins did not reduce the risk for heart disease or cancer. And for certain populations, taking specific nutrition supplements can be risky. For example, taking supplements that contain beta-carotene has been linked to an increased risk of lung cancer among those who have a history of smoking cigarettes.

Mitri explained that taking a daily multivitamin may also cause some digestive issues, "mainly if it contains above 100% of your Recommended Daily Allowance (RDA) in certain nutrients such as iron, zinc, or vitamin C." Exceeding the RDA may also negatively affect certain aspects of your health, like taking megadoses of vitamin D may be linked to the development of kidney stones.

Whether you should be popping a multivitamin depends on many factors, including your medical history and your diet. While it is true that some people may benefit from taking a multivitamin, that doesn't mean that it will help all people. Ultimately, the decision to take a multivitamin should involve weighing your specific risks and benefits with your healthcare provider and coming to the conclusion of what's best for you together.

Lauren Manaker is an award-winning registered dietitian and freelance writer who is passionate about providing evidence-based nutrition information in a fun and interesting way.