Improving your health can be a long and difficult road, so naturally, people would want to take as many shortcuts as possible. According to the National Institutes of Health, around one-third of American adults take multivitamins to supplement their diet. These dietary supplements contain a combination of various micronutrients, including vitamins, minerals, and other elements. These supplements have become extremely popular in recent years and are at the center of many health claims.
There is no standard scientific definition of a multivitamin. In the United States, they are supplements with three or more micronutrients that do not include hormones, herbs, or drugs. Additionally, each dose must be below the FDA’s tolerable upper intake level and cannot present a risk of adverse health effects. Essentially, this means that a multivitamin must contain only vitamins and minerals in safe amounts and not cause any issues. They come in a variety of forms, such as gummies, powders, liquids, and tablets.
Different companies provide formulas for various demographics. A multivitamin for adult males might not have the same composition as one for young females. In general, a multivitamin usually contains 13 vitamins and 16 minerals in various amounts. Interestingly, most multivitamins have low levels of calcium and magnesium because the pills would become too large otherwise. A significant problem with multivitamins is that the FDA doesn’t regulate dietary supplements. As a result, the actual multivitamin may have different levels of nutrients than the label states.
One of the most popular claims about multivitamins is that they help prevent heart disease. Despite conflicting studies, the consensus is that multivitamins do not, in fact, offer this benefit. One of the most important studies was the Physicians’ Health Study II, where over 14,000 doctors investigated the daily use of multivitamins and placebos for over a decade. Their results found no reductions in strokes, heart attacks, or mortality. In 2018, Circulation: Cardiovascular Quality and Outcomes published a meta-analysis of 45 years of multivitamin studies and the effects the supplements may have on various cardiovascular disease outcomes. They found that multivitamins don’t improve cardiovascular outcomes in the general population.
Another of the loftiest claims states that multivitamins can help prevent cancer. As with heart disease, many researchers are in disagreement. Results from the Physicians’ Health Study II showed that males were 8% less likely to receive a cancer diagnosis after regularly using a multivitamin. This effect was most prevalent in males with a history of cancer. In 2015, the U.S. Preventive Services Task Force analyzed studies involving around 450,000 people. Their analysis found no direct evidence that multivitamins could prevent cancer or cardiovascular disease.
Many other health claims appear with varying frequency. Some state that multivitamins prevent mental decline, improve life expectancy, or reduce the risk of having a child with autism spectrum disorder. While a handful of studies seem to support these claims, the evidence is weak. Many ongoing studies are attempting to corroborate or refute the statements, with one of the largest involving 22,000 males and females from across the United States. However, until results from these studies are available, there isn’t enough evidence to support most of these assertions.
In some cases, multivitamins may be harmful to those who use them regularly. Most companies use formulas aiming for optimal health effects for large population groups. However, this may not be ideal for subgroups such as children, pregnant women, people with conditions, or those taking medication. Long-term use of vitamin A and E supplements has links to shortened life expectancy and may increase the risk of lung cancer in those who smoke. Additionally, many of the more affordable brands contain dangerously high levels of nutrients. While rare, this can lead to acute overdose.
Understanding nutrient and multivitamin interactions can help prevent health issues. As an example, never drink milk or other dairy products before or shortly after taking a multivitamin. Calcium can make it difficult for the body to absorb certain ingredients from a multivitamin. Taking similar vitamin products together is more likely to lead to a vitamin overdose. While using a multivitamin that contains potassium, avoid salt substitutes. Finally, always read the label of any multivitamin product and only purchase reputable brands and formulas.
While multivitamins may not be ideal for the general population, a few select groups may benefit from them. Pregnant women usually need greater amounts of iron, folic acid, and other nutrients. As with most supplements, females who are pregnant or trying to become pregnant should speak with their doctor about using a prenatal multivitamin. Consulting with a physician is incredibly important as certain vitamin excesses or deficiencies may cause congenital disabilities.
Other groups who may find some benefit in multivitamins are children, older adults, sick individuals, or people on restrictive diets. Notably, infants and babies up to age two or three years are often not eating a varied diet, which can lead to various nutrient deficiencies. People who are vegetarian or vegan may have a similar issue because they are not able to receive nutrients from meat products. While there are substitutes available, it may be easier for these groups to take a multivitamin after consulting with a doctor or a licensed dietitian.
Most experts agree that the average person doesn’t need to take a multivitamin, at least not daily. At best, multivitamins are ineffective for the general population. At worst, they may be actively harming individuals who rely on them. While it is tempting to take a shortcut to better health, most evidence shows that good habits such as eating a healthy diet and maintaining an optimal weight are the most effective ways to achieve wellness.
This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.