In This ArticleView AllIn This ArticleWhat Is a Multivitamin?Health EffectsWhat to Look for
In This ArticleView All
View All
In This Article
What Is a Multivitamin?
Health Effects
What to Look for
Eating a healthy diet is the ultimate path to optimal nutrition. For those who may fall short on critical nutrients, multivitamins and multivitamin-mineral supplements (MVM) provide a means to fill in the gaps. Nearly one-third of Americans include MVMs in their wellness routine.
The U.S. market for dietary supplements, including vitamins, minerals or both, was estimated at a value of $53.58 billion for 2023 with growth continuing in the coming years.Popular kitchen cabinet staples are vitamin D, magnesium and omega-3 fatty acids, with multivitamins taking up about 43% of the market in sales.
While many brands promote MVMs for energy, athletic performance and immunity, general health and disease prevention are the primary reasons people take them routinely.A regular eating pattern full of whole grains, lean protein, fruits, vegetables, nuts and seeds may make a MVM unnecessary. Keep reading to learn more about multivitamins and what happens to your body when taking a multivitamin daily.
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Multivitamin mineral supplements are dietary supplements that contain unique combinations of vitamins, minerals or both, with each nutrient helping to meet a dietary need. Available in various forms such as capsules, gummies and liquid, MVMs are usually taken once a day, though some may recommend multiple daily dosages.
While the average person looks to multivitamins to get ahead of their health, other groups may be at high risk for poor nutrition and have a greater need for them. “For most people, a multivitamin isn’t necessary, but for some, like older adults, people who are experiencing low appetite or difficulty eating a balanced diet, from an illness or even pregnancy, a multivitamin can help fill in nutrition gaps,” saysKelsey Lorencz, RDN, a registered dietitian nutritionist at Graciously Nourished.
What Happens When You Take an MVM Every Day?
You May Have Better Immune Function
Zinc, vitamin C and vitamin D play significant roles in maintaining ahealthy immune function. Lacking these nutrients makes it harder for your body to fight illnesses. That’s because zinc and vitamin C deficiencies can cause oxidative stress, which happens when antioxidants and free radicals in the body are off their balance, leading to inflammation and disease. Vitamin C is more than a vitamin; it’s also an antioxidant that helps remove harmful free radicals that can wreak havoc on immune health.
In one study, 42 older adults were randomly placed into two groups, with 21 in one group receiving a MVM and the other 21 receiving a placebo. After 12 weeks, the researchers found that MVM supplementation improved blood levels of zinc and vitamin C; however, there weren’t any improvements in markers of immune function.
Moreover, vitamin D is often studied for its benefits in regulating gut function.When lacking, it can cause inflammation, potentially driving chronic diseases. Specifically, vitamin D is a nutrient of public health concern since recommended intakes can be challenging to achieve.This is partly because our bodies produce vitamin D when we’re exposed to a certain level of sunlight—so if you’re not in the sun long enough with enough skin exposure, your body won’t produce it. Some foods also contain vitamin D, but unless you’re eating enough of them, you might not accumulate enough of this vitamin.
You Might Experience Gastrointestinal Symptoms
Taking your daily multivitamin could cause tummy troubles, depending on the levels of nutrients it possesses. “If you are taking [multivitamins] in large doses and your body doesn’t need the extra, you may experience mild side effects such as nausea or stomach upset,” saysMelissa Mitri, M.S., RD, of Melissa Mitri Nutrition.
In a multivitamin, the following vitamins and minerals could create gastrointestinal symptoms in high doses.
If you’re planning to take a multivitamin, Mitri recommends looking for nutrients close to 100% of the RDA, as opposed to ones that go way over the RDA. Sticking to multivitamin brands that don’t overload you with nutrients is key to lessening stomach upset.
You May Boost Your Energy Levels
“People who begin to supplement with a multivitamin and have a specific deficiency may feel a difference in their energy level, but it’s not guaranteed,” says Mitri.
One study investigated MVM supplementation in 82 healthy, active adults, with 40 receiving a placebo and 42 receiving a MVM. After one month, they found MVM increased carbohydrate breakdown in males after 10 minutes of exercise and increased energy expenditure. Females taking MVMs reported reduced stress and lower mental tiredness; after 30 minutes of exercise, they were less physically tired.
Furthermore, some deficiencies, such as iron deficiency, can drop your energy levels, causing you to feel sluggish and tired. This study also saw higher ferritin (a measure of iron stores) levels after supplementing with MVM for a month.
You Might Have a Healthier Pregnancy
Data supports that MVM supplementation in pregnancy may reduce the chances of pregnancy complications such as anemia, intellectual disability, gestational diabetes, autism and neural tube defects.The American College of Obstetrics and Gynecology (ACOG) encourages taking prenatal vitamins before and during pregnancy.
You May Be Less Anxious
The unfortunate reality is that mental health issues are rising today. The good news is that more research continues to emerge on hownutrition can positively influencepsychological challenges.
A review study found that consuming adequate B vitamins and probiotics can reduce depression and anxiety symptoms and may help with sleep. The study looked at B vitamins as a complex, meaning it did not differentiate a specific B vitamin, such as niacin or B-12. You will find B-complex vitamins in a MVM, and may also find one with added probiotics.
Additionally research has found that high doses of vitamin D effectively improved anxiety symptoms.
You Might Have Sharper Brain Function
In a study on supplementation and brain function, researchers split 2,602 adults into three groups. One group took a 500-milligram cocoa extract supplement, one took a placebo, and the last took an MVM. After following all groups for three years, researchers found that daily MVM supplementation improved brainpower through executive function. Executive function aids in memory, attention, planning and focus. No significant differences were seen in the cocoa and placebo groups.
What to Look for in a Multivitamin
Some supplements do not mix well with certain medications or medical conditions, so always speak with your health care practitioner before starting a new supplement. They have a better idea of your medical history and health needs to help you make the best choice for yourself.
Before adding more vitamins to your supplement stash, here are some things to consider.
Choose Nutrients You May Lack
Depending on your lifestyle or health issues, you might be lacking some nutrients. For example, vegetarians and vegans are prone to deficiencies in iron andvitamin B12.
5 Sneaky Signs You Might Have a Vitamin D Deficiency
Stick to Certified Supplements with Safe Ingredients
Some supplements may contain contaminants like heavy metals. To avoid tainted supplements, look for signs on the label that state they have been verified.
“Whenchoosing a multivitamin, look for the USP or NSF independent verification seal of approval on the bottle. This ensures the product contains what it said it does and is held to the highest-quality standards,” says Mitri.
The Bottom Line
What happens to your body when you take a multivitamin every day could vary from renewed energy to more brainpower. While the research on multivitamins continues, daily multivitamins may not benefit everyone. The truth is that multivitamins may offer little benefit if you’re a healthy eater. Eating a wide variety of healthy foods is the first-line approach to supplying your body with the nutrition essentials. Talk to your medical provider about supplementation options if you have a poor appetite, digestion problems, food allergies, a new pregnancy, or are thinking about becoming pregnant.
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Sources
EatingWell uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable and trustworthy.
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