Multivitamins: Are They Worth Trying?


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If your eating patterns are erratic, you may wonder if adding a multivitamin can help ensure that all of your nutrient needs are met. Some people think of multivitamins as a back-up plan or insurance policy to make sure they get enough of each vitamin and mineral daily.

Below we explore whether this approach is necessary as well as whether or not you can get too much of a good thing. Read on to learn more about multivitamins and what the research says about taking them.

What Are Multivitamins?   

A multivitamin is a dietary supplement that includes a combination of different essential vitamins and minerals. There are a huge variety of multivitamins on store shelves, and they come in different formats including capsule, tablet, chewable, gummy, and liquid.

The exact nutrients and amount of each nutrient varies by multivitamin brand, so there is no one-size-fits-all answer as to what is inside. Some brands are basic vitamins and contain low doses of different vitamins and minerals, while others are branded as high-potency and have much larger doses of individual nutrients.

Nutrients Found in Multivitamins

Most multivitamins will have some combination of the following nutrients:

  • B Vitamins (B1, B2, B3, B5, B6, B12 and folate)
  • Calcium
  • Iron
  • Magnesium
  • Vitamin A
  • Vitamin C
  • Vitamin D
  • Vitamin E
  • Vitamin K
  • Zinc

They also may contain trace minerals such as selenium, copper, manganese, molybdenum, and chromium.

Some multivitamins also contain added herbs, probiotics, antioxidants, or glucosamine, and may be marketed for a specific population, such as for women, or for adults over age 65.

What the Research Says

Multivitamins are popular in the U.S. In fact, the Centers for Disease Control and Prevention (CDC) indicates that multivitamins are the most common type of dietary supplement used by all age groups. But are multivitamins necessary? For healthy adults eating a well-balanced diet with lots of variety, studies show that a multivitamin will not provide much additional benefit.

Some people choose to take multivitamins for disease prevention, but studies do not support this connection. A meta-analysis review study found insufficient evidence to support any benefits of multivitamins to help prevent heart disease or cancer in healthy adults with a varied diet. Another study tracked mental functioning over 12 years in people taking multivitamins and found no reduction in mental decline or memory loss.

Who May Benefit From Multivitamins?

Multivitamins are often recommended for people at risk of nutrient deficiencies, including:

  • People who are pregnant or trying to get pregnant.
  • People who are breastfeeding.
  • People who have a limited diet, poor appetite, or reduced access to a variety of foods.
  • People with a condition that limits nutrient absorption, such as celiac disease or colitis

Ironically, studies find that multivitamin users tend to have higher nutrient intakes from their diet alone, and that the populations at highest risk of nutritional inadequacy are the least likely to take multivitamins.

Instead of taking a multivitamin, healthcare professionals may advise you to take individual nutrients that your body may be lacking. For example, older adults may not absorb vitamin B12, and menstruation may cause excessive iron loss.

Likewise, in the U.S. one out of four people have vitamin D blood levels that are too low or inadequate for bone and overall health. In these cases, it may be more appropriate to take the specific nutrient rather than a multivitamin. Taking a multivitamin can sometimes provide extra nutrients that are unnecessary.

Potential Dangers 

Even when it is technically unnecessary, taking a basic low-dose broad-spectrum multivitamin should be safe for most healthy people. However, some multivitamins contain individual nutrients in dosages that are higher than what's recommended for health. These are often labeled as high-potency multivitamins, and can exceed the adequate intake level or the upper tolerable intake level for what is deemed to be safe.

Risks Associated With High Doses

Taking high doses of certain nutrients can be harmful or toxic. For example:

  • Excess vitamin A during pregnancy can increase the risk of birth defects in infants.
  • Too much vitamin D can lead to hypercalcemia (high calcium), which can cause vomiting, muscle weakness, psychiatric disturbances, and kidney stones.
  • Excess vitamin E can contribute to hemorrhagic strokes.
  • Too much magnesium can cause diarrhea, nausea, and abdominal cramping.
  • Very high calcium intakes may increase the risk of prostate cancer and heart disease.

It's also important to remember that there aren't any U.S. government health agencies or health professional organizations that promote the regular use of multivitamins. What's more, they are not regulated for safety or evaluated for the claims these products make.

Speak with a healthcare provider to see which individual vitamins or minerals you may need, or if a multivitamin is necessary. You also should check with a pharmacist before taking any supplements to ensure that your vitamins do not interfere with any prescription medications.

Multivitamins vs. Food 

Health professionals recommend getting nutrients from food before turning to supplements. As the name implies, multivitamins are meant to supplement a balanced diet, not replace it.

If you have troube meeting your vitamin and mineral needs through food alone, multivitamins can help, but they cannot replace a balanced, varied diet. Remember, food provides more than vitamins and minerals; foods also contain fiber, fluid, and phytonutrients that are also important.

While there are many benefits from the nutrients found in foods, there is less evidence that multivitamins have the same effect. For example, a meta-analysis of studies on multivitamins found little evidence that these supplements help prevent cardiovascular disease, whereas a balanced diet is positively associated with reduce risk of heart disease.

What Is a Balanced Diet?

According to the USDA, a balanced diet involves meeting your nutritional needs from nutrient-dense food and beverages. This includes choosing a variety of options from each food group, such as fruits, vegetables, grains, protein foods, and dairy or fortified soy alternatives.

A varied dietary pattern can help you achieve and maintain good health and reduce the risk of chronic diseases like heart disease, type 2 diabetes, osteoporosis, obesity, and some cancers. If you need help putting together an individualized eating plan, consider speaking with a registered dietitian.

A Word From Verywell

If you habitually eat a poor diet or know that you are not meeting your nutrient needs through food alone, a multivitamin may be a good idea. But if you eat a well-balanced and varied diet, there's likely no reason to take a multivitamin, too.

If you are deficient in an individual vitamin or mineral, it makes more sense to take it rather than rely on a broad-spectrum multivitamin that contains nutrients you already get enough of. Excess amounts of fat-soluble vitamins (A, D, E, and K) get stored in tissue and can build up to toxic levels, while water-soluble vitamins (Bs and C) get flushed away in urine and are ultimately wasted.

Frequently Asked Questions

  • Should everyone be taking a multivitamin?

    A basic low-dose multivitamin should be safe for most healthy people. But it is not necessary if you have a well-balanced, varied diet.

  • What happens to your body when you start taking vitamins?

    If you are deficient in a specific vitamin or mineral, taking a multivitamin will help fill the gaps. Excessive amounts of fat-soluble vitamins (A, D, E, and K) get stored in tissue and can build up to toxic levels, while excessive amounts of water-soluble vitamins (Bs and C) get flushed away in urine.

  • How do I know if I need a multivitamin?

    If you have a well-balanced, varied diet, you may not need a multivitamin. If you are pregnant, breastfeeding, have a limited diet or poor appetite, or have a medical condition that limits nutrient absorption, work with a healthcare provider or dietitian to choose the right supplements for your optimal health.

16 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Institutes of Health, Office of Dietary Supplements. Multivitamin/mineral supplements.

  2. National Institutes of Health, Office of Dietary Supplements. Multivitamin/mineral supplements fact sheet for health professionals.

  3. Bailey RL. Overview of dietary assessment methods for measuring intakes of foods, beverages, and dietary supplements in research studiesCurrent Opinion in Biotechnology. 2021;70:91-96. doi:10.1016/j.copbio.2021.02.007

  4. Centers for Disease Control and Prevention. Dietary supplement use among adults.

  5. Chen F, Du M, Blumberg JB, et al. Association among dietary supplement use, nutrient intake, and mortality among U.S. adultsAnn Intern Med. 2019;170(9):604-613. dol:10.7326/M18-2478

  6. Fortmann SP, Burda BU, Senger CA, Lin JS, Whitlock EP. Vitamin and mineral supplements in the primary prevention of cardiovascular disease and cancer: an updated systematic evidence review for the U. S. Preventive services task force. Ann Intern Med. 2013;159(12):824-834. doi:10.7326/0003-4819-159-12-201312170-00729

  7. Grodstein F, O’Brien J, Kang JH, et al. A randomized trial of long-term multivitamin supplementation and cognitive function in men: the physicians’ health study ii. Ann Intern Med. 2013;159(12):806-814. doi:10.7326/0003-4819-159-12-201312170-00006

  8. National Institute of Health, Office of Dietary Supplements. Vitamin D.

  9. National Institutes of Health Office of Dietary Supplements. Vitamin D fact sheet for health professionals.

  10. National Institutes of Health, Office of Dietary Supplements. Vitamin E fact sheet for health professionals.

  11. National Institutes of Health, Office of Dietary Supplements. Magnesium fact sheet for health professionals.

  12. National Institutes of Health, Office of Dietary Supplements. Calcium fact sheet for health professionals.

  13. Jenkins D et al. Supplemental vitamins and minerals for CVD prevention and treatment. Journal of the American College of Cardiology. 2018;71(22):2570-2584. doi.10.1016/j.jacc.2018.04.020

  14. USDA. Dietary Guidelines for Americans, 202-2025.

  15. USDA. What is a healthy diet?

  16. National Institutes of Health. Biochemistry water soluble vitamins.

By Cara Rosenbloom, RD
 Cara Rosenbloom RD is a dietitian, journalist, book author, and the founder of Words to Eat By, a nutrition communications company in Toronto, ON.