Discover 15 science-backed reasons to take a multivitamin—from energy and heart health to the bones and brain.
In a perfect world, our daily diet would deliver every essential vitamin, mineral, and phytonutrient we need. But in reality, busy schedules, modern farming practices, and soil depletion can leave nutritional gaps.
That’s where a high-quality multivitamin steps in—covering nutritional gaps, supporting overall health, and preventing deficiencies. Far from being “just expensive urine”—a myth debunked by numerous studies—multivitamins play a key role in preserving your health.
In fact health and fitness expert Dr. Rhonda Patrick recently said this:
“Everyone should take a multivitamin. It’s a simple, effective way to support long-term cognitive health, especially for middle-aged and older adults. About a decade ago, multivitamins were deemed useless or harmful. Recent large, randomized controlled studies provide irrefutable evidence to the contrary. Adults taking a standard multivitamin for 2 years improved cognition and episodic memory, equivalent to a 2-year reduction in cognitive aging.
Multivitamins provide micronutrients missing from our diets—those important for metabolism, neurotransmission, and most importantly, reducing DNA damage and oxidative stress that contribute to aging. Think of it as nutritional insurance for your body and brain. And don’t let anyone tell you it’s just making “expensive urine.”
In this article we’ll explore 15 science-backed reasons why adding a multivitamin to your routine could be one of the simplest, most effective investments in your health.
!5 Key Reasons to Take a Multivitamin
Here are 15 reasons to take a multivitamin:
Fills Nutritional Gaps
Many people—even with healthy eating habits—fall short of meeting micronutrient needs due to modern diets, soil depletion, and busy lifestyles. A daily multivitamin serves as a safety net, ensuring you consistently get essential vitamins and minerals.
Cognition & Anti-Aging
Studies show that older adults taking daily multivitamins experience significantly slower cognitive aging—about a two-year delay—and especially in episodic memory and overall cognition. Meta-analyses have confirmed these effects. One report notes that “Results showed a statistically significant benefit for cognition among participants taking the multi-vitamin compared to placebo, suggesting that a multi-vitamin could help prevent memory loss and slow cognitive aging among older adults.”
Another report also cites cognition and memory improvements in participants who took multivitamins.
Reduces Oxidative Stress
Multivitamins often include antioxidants C, E, selenium, and beta-carotene, that help offset the negative impacts of free radicals. Studies find that multivitamins can help enrich antioxidant biomarkers. One report notes that “Multivitamin supplementation is a logical strategy to increase antioxidant pools.”
Protects Telomeres
Multivitamins may protect against telomere shortening by mediating oxidative stress, according to a report in the Journal of Dietary Supplements (Taylor & Francis): “High vitamin consumption has been associated with longer telomere length, whereas oxidative stress is associated with telomere shortening.” The study also found that multivitamin mixtures protected “against oxidative stress-mediated telomere shortening in cell culture.”
Immune Support
Key nutrients like vitamins C, D, E, zinc, selenium, and vitamin A support immune health by enhancing white blood cell production, reducing inflammation, and defending against infections. Ensuring against micronutrient-deficiencies can strengthen the immune system.
Aids Eye Health & Vision
Nutrients like vitamins A, C, E, zinc, lutein, and omega-3s help maintain vision and may slow the progression of age-related macular degeneration and cataracts. Studies show that long-term multivitamin use may reduce these risks.
One report notes that “Before you ask your doctor about taking mega-doses of vision supplements, take a look at your multivitamin, if you use one. You’ll probably find you’re already taking several of the following nutrients for healthy eyes.” In other words, most of the best eye micronutrients can be found in a high-quality multivitamin.
Pregnancy Support
Folic acid in multivitamins is critical in early pregnancy to prevent neural tube defects. The CDC recommends 400–800 µg/day, starting at least one month before conception. Multivitamins also usually contain iron, iodine, and vitamin D—nutrients that are otherwise hard to obtain in adequate amounts during pregnancy. Studies show that multivitamins help prevent neural tube defects.
Boosts Energy & Reduces Fatigue
B-complex vitamins, iron, and magnesium—common ingredients in multivitamins—help convert food into usable energy, reducing tiredness and improving vitality. Most quality multivitamins cover the B complex spectrum.
Promotes Strong Bones & Muscle Function
Multivitamins containing vitamin D, calcium, magnesium, and vitamin K support bone density and muscle contraction/relaxation—a key benefit as we age.
Supports Mood & Stress Management
B vitamins in multivitamin supplements—especially B6, B12, and folate—play a key role in neurotransmitter production like serotonin, which can help reduce anxiety, stress, and support mental well-being.
Potentially Reduces Cancer Risk
Micronutrient deficiencies can lead to an overall breakdown in metabolic health, including the immune system and cellular efficiency. This can lead to an increased risk of disease, including cancer. An article in the Nutrition Journal notes that “filling in relatively small but critical nutritional gaps” with multivitamins may help prevent anemia, osteoporosis, neural tube defects, cancers, and other chronic diseases.
Heart Health
Certain vitamins and minerals like B6, B12, folic acid, magnesium, potassium, C, and E—help regulate homocysteine, blood pressure, and oxidative stress, promoting cardiovascular well-being.
Healthy Hair, Skin, and Nails
Micronutrient deficiencies can do a number on your hair, skin, and nails. Vitamins like A, C, E, biotin, and niacin support collagen formation, skin hydration, hair strength, and nail health, giving you that inner glow.
Offsets Obesity
Taking a multivitamin may help offset obesity by addressing subtle micronutrient deficiencies that can disrupt metabolism, appetite regulation, and energy balance. Low levels of nutrients like vitamin D, magnesium, and B-complex vitamins are linked to increased fat storage, insulin resistance, and cravings for calorie-dense foods.
By ensuring the body has the vitamins and minerals it needs for optimal metabolic function, a multivitamin can support more efficient energy use, help stabilize blood sugar, and reduce overeating driven by nutrient gaps—factors that collectively make maintaining a healthy weight easier.
Lifespan Extension
Taking a multivitamin may extend lifespan by providing a steady supply of essential vitamins and minerals that protect cells from damage, support DNA repair, and optimize metabolic and immune functions. Nutrients like antioxidants (vitamins C, E, and selenium) help reduce oxidative stress, while B vitamins aid in methylation and energy production—both crucial for slowing cellular aging. By filling dietary gaps that, over time, contribute to chronic disease risk, multivitamins can help maintain organ health, reduce inflammation, and promote the physiological resilience needed for longevity.
Final Thoughts
Multivitamins can act as a meaningful supplement in a “better safe-than-sorry” approach—filling nutritional voids, supporting brain health, protecting specific at-risk groups (like older adults and pregnant individuals), and combating oxidative damage.
That said, they are never a substitute for a balanced diet, and the magnitude of benefits varies depending on age, health status, and baseline nutrient levels.
Always choose quality supplements tailored to your individual needs and consult with a healthcare professional before starting a new regimen.
Cautionary Notes
If you have medical conditions or take prescription drugs, you should consult your physician before taking supplements. It’s also important to vet your brands, do your research, read ingredient lists, and check dosages.
Here are some considerations:
Not a Substitute for a Healthy Diet
Supplements can’t replicate all the phytochemicals, fiber, and synergistic nutrient effects found in whole foods. Relying solely on pills while eating poorly will limit results.
Risk of Excess
Fat-soluble vitamins (A, D, E, and K) and certain minerals can accumulate to toxic levels if taken in high doses. For example, too much vitamin A can harm the liver, cause birth defects, or impair bone health.
Potential Interactions with Medications
Multivitamins can interact with prescriptions, such as blood thinners (vitamin K), antibiotics (zinc, calcium), or thyroid medication (iron). Always consult your healthcare provider if you’re on medication.
Quality Varies Widely
Supplement manufacturing isn’t as tightly regulated as pharmaceuticals in many countries. Some products contain inaccurate dosages or contaminants. Look for third-party testing (USP, NSF, ConsumerLab).
Population-Specific Concerns
- Smokers should avoid high-dose beta-carotene due to increased lung cancer risk.
- People with kidney disease may need to avoid excess minerals like potassium or phosphorus.
- Pregnant individuals should ensure their multivitamin has safe nutrient forms and dosages (especially vitamin A).
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The medical and health topics covered on the PlateofGrass website and blog have not been evaluated by the FDA and are not intended to prevent or cure any disease. This article and its content is presented ‘as is’ for informational purposes only.
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