Do I Need a Multivitamin If I Eat Healthy? The Honest Answer

If you eat a genuinely balanced diet, a standard multivitamin is unnecessary for most healthy adults under 50. Three nutrients are the real exceptions: vitamin D, which food barely provides; vitamin B12, essential for vegans and adults over 50; and possibly omega-3s. Take those individually, not in a shotgun pill.

The US Preventive Services Task Force recommended against routine vitamin supplementation for healthy adults without known deficiencies in 2022, and a JAMA study published the following year tracked 390,000 participants and found no reduction in all-cause mortality among regular multivitamin users. That second result is the one that tends to stop people mid-scoop: the pills are not merely neutral on paper, they are measurably doing nothing for the outcome most people actually care about.

Vitamin D is where the "I eat well" argument falls apart, because diet is not the main source. Sun exposure is the main source, and it is unreliable above roughly 37°N latitude from November through February, a band that covers about 40% of Americans. The RDA is 600 IU (15 mcg) for adults under 70 and 800 IU (20 mcg) above that. A serving of salmon gets you partway there; a bowl of kale does not.

B12 is the other genuine gap, and it is not about eating well so much as eating what. Vegans run roughly seven times the deficiency risk of omnivores, and absorption declines with age regardless of diet, which is why the NIH tells adults over 50 to get B12 from fortified foods or a supplement rather than relying on meat and dairy.

• USPSTF position: The US Preventive Services Task Force recommends against routine vitamin supplementation for healthy adults without nutrient deficiencies, as of its 2022 recommendation statement.
• No mortality benefit: A 2023 JAMA study of 390,000 participants found daily multivitamins produced no reduction in all-cause mortality.
• Winter latitude gap: Vitamin D from sun exposure is unreliable above 37°N from November to February, affecting roughly 40% of Americans.
• B12 by age: The NIH advises adults over 50 to obtain vitamin B12 from fortified foods or supplements because absorption declines with age.
• Vegan risk: Vegans have about a 7-fold higher risk of B12 deficiency than omnivores.

What does a “balanced diet” actually mean in nutrient terms?

Strip the marketing away and “balanced” is a nutrient checklist, not a feeling. The working definition used by most dietitians: at least five servings of fruit and vegetables a day, three or more of whole grains, a palm-sized portion of lean protein at two meals, and fats from nuts, olive oil or oily fish rather than from a fryer. Hit that on most days and you clear the RDA for vitamin C, folate, magnesium, calcium, iron and the B-complex vitamins without thinking about it. A large salad, a bowl of oats, an egg and a chicken thigh will do it.

The good news is that this does not need to be a seven-day-perfect performance. Your body stores the fat-soluble vitamins—A, D, E, K—for weeks or months, and B12 reserves in the liver can carry an adult for three to five years. A weekend of pizza and beer does not empty the tank. What matters is the pattern across a month, not the precision of a single Tuesday.

The honest part: most people think they eat better than they do

Here is the uncomfortable number. NHANES, the CDC’s rolling national nutrition survey, has repeatedly found that fewer than 1 in 10 American adults meet the recommended intake for vegetables. Roughly 90% fall short, and the shortfall is largest among people who describe their own diet as “healthy.” That gap matters, because the case against a multivitamin rests entirely on the premise that you are actually eating the diet you think you are.

So test it rather than assume it. Track every vegetable and fruit serving for seven days, count the whole-grain portions, and note how often fish appears. If you clear five servings of produce on at least five of those days, the USPSTF’s 2022 Grade D recommendation against routine multivitamin use for healthy adults applies directly to you—and the JAMA 2023 analysis of 390,124 participants, which found no mortality benefit from daily multivitamins, is your number. If you do not clear it, the answer is not a $0.10–$0.30 pill. It is more vegetables, plus targeted testing for the two or three nutrients that food genuinely struggles to deliver.

The 3 nutrients that are genuinely hard to get from food alone

The case for a multivitamin gets stronger once you narrow it to nutrients where diet alone demonstrably fails most people. That is a much shorter list than the 20-plus ingredients crammed into a typical Centrum tablet. Three nutrients keep showing up in the research, and they have almost nothing in common except that food sources are narrow.

• Vitamin D. The only reliable dietary sources are fatty fish (wild salmon runs roughly 600-1,000 IU per 3.5 oz), fortified dairy, and mushrooms exposed to UV light. The NIH RDA is 600 IU (15 mcg) for adults 19-70 and 800 IU (20 mcg) for 71 and older, but you will not hit those numbers from vegetables and whole grains. The CDC reported in 2021 that roughly 40% of Americans have insufficient vitamin D levels, and serum levels fall in winter when the sun angle in most of the US is too low for meaningful cutaneous synthesis. A standalone D3 capsule costs $0.03-$0.05 per day, far less than the multivitamin that only contains 400 IU of it.
• Vitamin B12. This is the nutrient with the clearest justification for supplementation in specific groups. B12 occurs naturally almost exclusively in animal products, so strict vegans and vegetarians who eat little dairy or eggs are at real risk of deficiency. A 2021 study in the European Journal of Clinical Nutrition found vegans were roughly seven times more likely to be deficient than omnivores. Adults over 50 also need supplemental B12 because age-related atrophic gastritis impairs absorption of food-bound B12 even in meat eaters. The RDA is 2.4 mcg/day for adults, 2.6 mcg for pregnancy, and 2.8 mcg during lactation (NIH, 2023), which is a trivially small dose to cover with a $0.05 tablet or a fortified cereal.
• Omega-3s (EPA and DHA). This is the murkiest of the three. The NIH RDA of 1.6 g/day for men and 1.1 g/day for women refers to alpha-linolenic acid (ALA), the plant form found in flaxseed and walnuts, not the EPA and DHA that carry most of the cardiovascular evidence. ALA converts to EPA at roughly 5-10% efficiency and to DHA at under 0.5%, so a tablespoon of flax oil is not the same as a serving of salmon. Two servings of fatty fish per week is the standard recommendation, and NHANES data consistently show most adults fall well short. Whether that shortfall translates into disease risk is genuinely unresolved.
• Iron. Worth naming specifically to say that most well-nourished adults should not be supplementing it at all. Menstruating women, pregnant women, and people with diagnosed anemia are the exceptions. Anyone else with a Western diet is unlikely to be low, and excess iron accumulates in the liver and has been linked to cardiovascular events.
• Calcium and magnesium. These get trotted out as deficiencies-in-waiting, but leafy greens, dairy, legumes, and whole grains cover both for anyone eating a varied diet. Unless you are lactose intolerant, vegan, or on a proton-pump inhibitor long term, you are almost certainly fine. Magnesium deficiency is mostly a lab artifact; serum magnesium is a poor marker of total body stores.
• Folate. The case here is narrow and already handled by food fortification. Since the FDA mandated folic acid fortification of enriched grains in 1998, neural tube defects fell by roughly 35% in the US. Women who might become pregnant should get 400 mcg from a supplement or fortified food, but for everyone else the dietary supply is more than adequate.
• What a multivitamin does not include. If you were buying the pill for omega-3s, you wasted your money: standard multivitamins contain no EPA or DHA, and the ones that claim to have "fish oil" typically deliver under 100 mg, which is not a therapeutic dose. The three nutrients above are better bought as three separate, cheap products.

The item people get wrong most often is vitamin D. They assume the 400 IU in their multivitamin is meaningful, but it is half the RDA for a 40-year-old and does not reliably move serum 25(OH)D into the sufficient range for someone starting below 20 ng/mL. The better move is a 1,000-2,000 IU standalone D3, taken with a fat-containing meal, and a blood test roughly every six months to see where you actually land. Dosing blind for years is how people end up at 80 ng/mL and slightly toxic.

Do multivitamins actually improve health outcomes?

The short answer from the trial literature is no, at least not for death, heart attacks, or cancer in people who already eat well. In 2022 the U.S. Preventive Services Task Force reviewed 84 studies and issued a Grade D recommendation against routine multivitamin use for the prevention of cardiovascular disease or cancer in healthy, non-pregnant adults. Grade D means the task force actively recommends against it — not "insufficient evidence," but "don't bother." That recommendation still stood as of the task force's 2026 review cycle, with no new trial data strong enough to reverse it.

The mortality picture is the same. A 2023 cohort study published in JAMA tracked 390,124 adults over roughly two decades and found no association between daily multivitamin use and lower all-cause mortality. Not a small effect that missed significance — no effect. If the pills were doing something meaningful for longevity, a cohort that size would have caught it. Meanwhile, the National Health and Nutrition Examination Survey has repeatedly shown that the people most likely to take a multivitamin are the ones whose diets already cover the bases, which is the exact population least likely to benefit.

Where the evidence turns negative

Some formulations are worse than useless. High-dose beta-carotene supplements increased lung cancer incidence in smokers in both the CARET trial (stopped early in 1996) and the ATBC trial in Finland, which reported an 18% higher lung cancer rate among male smokers taking beta-carotene versus placebo. High-dose vitamin A has been linked to hip fracture risk and birth defects; high-dose vitamin E, to increased bleeding risk and in one 2005 meta-analysis a slightly higher all-cause mortality. These are dose problems, not multivitamin problems per se — a standard one-a-day contains beta-carotene at 2,500 to 5,000 IU, far below CARET's 30 mg. But the pattern matters: when a nutrient is already adequate, adding more doesn't top up a tank. It just adds a variable you can't control.

The honest trade-off is between two groups. If you're a healthy non-smoker under 50 eating vegetables, whole grains, and some animal or fortified protein most days, a standard multivitamin at $0.10 to $0.30 per day buys you expensive urine. If you're over 70, pregnant, vegan, or on a proton-pump inhibitor, the calculus shifts, and you should be testing and targeting specific nutrients rather than taking a shotgun pill. The pill is not the problem. Taking one without knowing which nutrient you're actually short on is.

Who might still benefit from a multivitamin?

The USPSTF's 2022 Grade D recommendation against routine multivitamin use applies to healthy, non-pregnant adults. It says nothing about people whose requirements exceed what food can realistically deliver, or whose bodies absorb nutrients poorly. That group is smaller than the supplement industry implies, but it is not empty.

• Pregnant women and those trying to conceive. Folate requirements rise from 400 mcg to 600 mcg daily, and iron needs jump from 18 mg to 27 mg. A prenatal vitamin covers both. Neural tube defects like spina bifida develop in the first 28 days of pregnancy, often before a woman knows she is pregnant, so folic acid supplementation is recommended for anyone who could become pregnant. This is one case where "eat more spinach" is not a serious substitute for a pill.
• Adults over 50. Stomach acid production declines with age, and that acid is what liberates B12 from food proteins. The NIH RDA stays at 2.4 mcg for adults, but after 50 the recommendation shifts toward crystalline B12 in fortified foods or supplements, which bypasses the acid step entirely. Vitamin D needs also rise to 800 IU (20 mcg) at 71, and calcium absorption drops. A standard multivitamin covers the B12 and D reasonably well; it usually does not carry enough calcium to matter.
• Vegans and strict vegetarians. B12 occurs naturally almost exclusively in animal foods. A 2021 study in the European Journal of Clinical Nutrition found B12 deficiency rates about 7 times higher in vegans than omnivores. Iron, zinc and omega-3s are also at risk: plant iron is non-heme and absorbed at roughly half the rate of heme iron, and the ALA in flax and walnuts converts to EPA and DHA at under 10 percent efficiency. A B12 supplement is non-negotiable here; a general multivitamin is one way to get it, though a standalone 1,000 mcg cyanocobalamin tablet costs a few cents.
• People with malabsorption conditions. Celiac disease damages the intestinal villi that absorb iron, folate, calcium and fat-soluble vitamins. Crohn's disease and ulcerative colitis can affect any segment of the gut, and surgical resection removes absorptive surface permanently. Ulcerative colitis patients who have had a colectomy and ileal pouch may need B12 injections rather than oral pills. A gastroenterologist typically monitors levels directly rather than prescribing blind supplementation.
• Bariatric surgery patients. Roux-en-Y gastric bypass reduces stomach acid, bypasses the duodenum where iron and calcium are absorbed, and cuts intrinsic factor production. The American Society for Metabolic and Bariatric Surgery recommends lifelong supplementation, usually a bariatric-specific multivitamin with higher iron, calcium citrate, B12 and D than a standard Centrum. Off-the-shelf multivitamins often fall short of these targets.
• People on long-term medication that depletes nutrients. Proton pump inhibitors like omeprazole reduce B12 and magnesium absorption over years of use. Metformin interferes with B12. Loop diuretics increase urinary magnesium and potassium loss. A doctor who knows the prescription history can decide whether a targeted supplement or a full multivitamin makes more sense.
• Adults over 65 with poor appetite or limited diet. The Elderly Nutrition Program and NHANES data consistently show that a meaningful fraction of older adults fall below the EAR for several vitamins, often because food intake drops with age, taste changes, or dental problems. This is a case where the diet itself is the problem, not the nutrient density of the food.

The item people get wrong most often is pregnancy. A prenatal vitamin is not a general multivitamin with a pink label. It has higher folate, higher iron, and controlled vitamin A (too much retinol can cause birth defects, so prenatals use beta-carotene or lower-dose retinol). Taking a standard multivitamin plus a separate folic acid pill sounds equivalent but often is not, because the folate dose in a normal multivitamin is 400 mcg, below the 600 mcg prenatal target. If you are pregnant or trying to conceive, buy a product labelled prenatal and check the folate and iron numbers on the back.

How does the cost of a multivitamin compare to targeted supplements?

A Centrum Adult 200-count bottle runs $18.99 at CVS in September 2026, which works out to $0.095 per tablet. Amazon's own-brand One Daily is cheaper at $13.49 for 300 tablets, or $0.045 daily. A single 1,000 IU vitamin D3 tablet from Nature Made costs $0.032 per day on Amazon's 650-count bottle; a 1,000 mcg B12 sublingual from the same brand runs $0.041 per day. Nordic Naturals Ultimate Omega costs about $0.55 per day at 1,100 mg combined EPA and DHA — an order of magnitude higher than anything else in the stack.

The clear winner is dropping the multivitamin entirely if you eat a mixed diet and get sun exposure. A Centrum habit costs $16 to $35 a year, and USPSTF's 2022 Grade D recommendation against routine multivitamin use for healthy adults, plus the JAMA 2023 analysis of 390,124 participants showing no mortality benefit, means you are paying for nothing measurable. Buying D3 and B12 separately beats the multivitamin on price per nutrient — $0.032 and $0.041 against $0.045–$0.095 — but the spread is only a few dollars annually, so the real argument is not price, it is that you stop taking eleven other vitamins you did not ask for and did not need. The one case where this flips is omega-3. If you are buying a real dose of EPA and DHA rather than the 200–300 mg in a typical multivitamin, targeted fish oil costs six to twelve times more, and a vegan who needs both B12 (deficiency rates roughly 7x higher than omnivores per the 2021 European Journal of Clinical Nutrition analysis) and algal omega-3 will spend $300–$400 a year on targeted pills alone. For everyone else, the annual savings from skipping the multivitamin are small — but so is the multivitamin's benefit.

Can you get too much of a good thing from multivitamins?

The framing that supplements can only help, never hurt, falls apart the moment you look at fat-soluble vitamins. Vitamin A, D, E and K are stored in liver and adipose tissue rather than excreted in urine, so a daily dose above what the body needs accumulates. Preformed vitamin A (retinol, retinyl palmitate) is the worst offender in a standard multivitamin: the tolerable upper intake level is 3,000 mcg RAE per day for adults, and chronic intake above that has been linked to liver damage, bone pain, and reduced bone mineral density. A single Centrum Adult tablet carries roughly 1,050 mcg RAE of preformed vitamin A, which leaves very little headroom if you also eat liver, fortified cereals, or drink milk. Beta-carotene from plants does not carry the same risk because conversion is regulated, but that distinction matters little when a pill label lists "vitamin A" without specifying the source.

Minerals bring a different problem, because the risk is not accumulation alone but competition. Iron has a tolerable upper limit of 45 mg/day for adults, and while premenopausal women lose iron through menstruation, men and postmenopausal women have no routine excretion pathway. The result is a slow build toward hemochromatosis-range ferritin in people who carry the HFE mutations (roughly 1 in 200 of Northern European descent) and even in some who do not. Zinc is subtler: the upper limit is 40 mg/day, and intake consistently above that impairs copper absorption, which can produce anemia and neuropathy over months. A multivitamin with 15 mg of zinc plus a zinc lozenge during cold season plus a fortified cereal can push someone past that line without any single product looking unreasonable.

What this means for the pill in your cabinet

Most standard multivitamins are formulated at or below these upper limits, so a single daily tablet is unlikely to cause acute harm in a healthy adult. The real exposure comes from stacking: a multivitamin plus a separate vitamin D capsule plus a B-complex plus a zinc lozenge plus fortified foods. That combination is common among exactly the health-conscious readers most likely to be asking this question. Read the label for preformed vitamin A, iron, and zinc, and if you are already eating liver, red meat, or fortified cereal regularly, the totals add up faster than the marketing suggests.

If you are taking a multivitamin purely out of habit, the safest move is to stop and replace it with targeted supplementation only where you have a documented gap. Vitamin D and B12 are the two nutrients worth testing for, and neither carries the accumulation risk that vitamin A or iron does at normal doses. That shift also cuts your daily cost from the $0.10–$0.30 range of a standard multivitamin to the $0.03–$0.10 range of a single-nutrient tablet, which is a rare case where the cheaper option is also the safer one.

What should you do instead of taking a multivitamin?

This applies to anyone who has read the previous sections and decided the shotgun pill is not worth $36–$110 a year. What you need before starting: a recent blood panel, a rough idea of what you actually eat in a week, and about 20 minutes with a doctor or a lab requisition form. Nothing here requires a subscription, an app, or a nutritionist.

1. Get a blood test before you buy anything. Ask for serum 25-hydroxyvitamin D, serum B12 (or methylmalonic acid if B12 is borderline), ferritin, and a complete blood count. In the US, a self-ordered panel through Labcorp or Quest runs roughly $150–$250 without insurance; with a doctor's order and insurance, often $0–$40. Ferritin matters because iron deficiency without anemia is common in menstruating women and shows up as fatigue long before hemoglobin drops. Do not supplement iron on a hunch. Iron overload is real and hard to undo.
2. Check vitamin D first, because deficiency is the one most likely to show up. The CDC's 2021 analysis of NHANES data put insufficient vitamin D at roughly 40% of the US population, with the highest rates in people with darker skin, those living above 37° latitude in winter, and anyone who works indoors. If your 25(OH)D comes back below 20 ng/mL, the fix is 1,000–2,000 IU daily, which costs about $0.03–$0.05 per day in tablet form. The RDA is 600 IU (15 mcg) for adults 19–70 and 800 IU (20 mcg) for 71 and older, per the NIH Office of Dietary Supplements.
3. Sort out B12 if you eat plant-based, take metformin, or are over 60. The adult RDA is 2.4 mcg per day (2.6 mcg pregnant, 2.8 mcg lactating). That is trivially easy from a salmon fillet or a glass of milk, but nearly impossible from unfortified plants. A 2021 paper in the European Journal of Clinical Nutrition found vegans roughly 7 times more likely to be deficient than omnivores. A cyanocobalamin tablet at 1,000 mcg once or twice a week is more than enough and costs pennies.
4. Eat two servings of fatty fish per week if you eat fish. That is roughly 8 oz total of salmon, sardines, mackerel, or herring, and it covers the omega-3 RDA of 1.6 g/day for men and 1.1 g/day for women in ALA terms while also delivering EPA and DHA that plant sources do not. Two cans of sardines cost about $3. If you do not eat fish, an algae-based EPA/DHA capsule at 500 mg combined runs $0.15–$0.40 per day. Flaxseed and walnuts supply ALA only, and conversion to EPA is poor — often under 10%.
5. If you are vegan, lean on fortified foods before pills. A cup of fortified soy or oat milk typically carries 1–3 mcg of B12 and 100–120 IU of vitamin D. Nutritional yeast, fortified according to the Vegan Society's standard, delivers 5–10 mcg of B12 per 2-tablespoon serving. Two cups of fortified plant milk plus a spoon of nutritional yeast most days closes the B12 gap without a capsule. Check the label: not all brands fortify.
6. Recheck your levels 8–12 weeks after starting any supplement, then annually. This is the step people skip. Vitamin D takes about 8 weeks to reach a new steady state; B12 responds faster. A recheck of just 25(OH)D and B12 runs $40–$80 self-pay. Without it you are guessing, and the guess is often wrong in both directions — some people need 5,000 IU to move their level, others hit 60 ng/mL on 1,000 IU.
7. Adjust after dietary changes. Going vegan, starting metformin, having bariatric surgery, or moving to a northern latitude all change your requirements. Recheck within 6 months of any of those, not on the calendar.

The failure mode is treating one abnormal result as a permanent prescription. Someone tests low on vitamin D in February, starts 5,000 IU, never rechecks, and by August is sitting at 80 ng/mL — above the 20–50 ng/mL range most labs call normal, and into territory where the Endocrine Society advises backing off. Supplement dose is not a set point. It is a response to a measurement, and the measurement moves with the seasons, your kitchen, and your latitude.

Which specific nutrients are worth testing for?

Testing only makes sense when the result would change what you do. A vitamin D result below 20 ng/mL means a supplement; 42 ng/mL means nothing. A ferritin of 11 ng/mL in a menstruating woman explains fatigue that a multivitamin would never fix. The panels that check twenty vitamins at once mostly generate noise and a bill. These six markers are the ones with real clinical consequences.

• 25-hydroxyvitamin D. This is the standard test, and it is the one worth paying for. The Endocrine Society and most US labs define sufficiency as 20–50 ng/mL; below 20 ng/mL is deficiency. The CDC's 2021 NHANES analysis put roughly 40% of Americans in the insufficient range, which is why this marker tops the list. The RDA is 600 IU (15 mcg) daily for adults 19–70 and 800 IU (20 mcg) for 71 and older, but the dose you need to correct a low reading is a conversation with a clinician, not a label.
• Serum B12, with a caveat. Total serum B12 is cheap and widely ordered, but it misses a meaningful slice of true deficiency. Levels can look normal while tissue stores are depleted, particularly in vegans and in people on long-term metformin or proton-pump inhibitors.
• Methylmalonic acid (MMA). When B12 is borderline (roughly 200–400 pg/mL) and symptoms exist, MMA is the more sensitive follow-up. It rises before serum B12 falls. It costs more, and it is not a first-line screen, but it resolves the ambiguity serum B12 leaves behind.
• Ferritin. Ferritin reflects stored iron and drops before hemoglobin does, so it catches iron depletion months before anemia shows on a CBC. A ferritin under 30 ng/mL is commonly treated as iron deficiency even when hemoglobin is normal. This matters most for menstruating women, endurance athletes, and regular blood donors.
• Folate. Worth checking if you are pregnant, planning pregnancy, or drink heavily. Otherwise, in someone eating leafy greens and fortified grains, it is rarely low and rarely actionable.
• Calcium and magnesium. Serum calcium is tightly regulated and almost never abnormal from diet alone; serum magnesium is a poor proxy for total body magnesium. Routine testing of either in a healthy adult with a balanced diet is usually money spent on reassurance.

The marker people most often get wrong is B12, and the error runs in both directions. A "normal" serum B12 prompts people to skip supplementation when MMA would have flagged a real deficit; a mildly elevated B12 in someone taking a supplement gets read as a problem when it is just the pill. If you are vegan, the case for testing is stronger than for anyone else, since deficiency rates run about seven times higher than in omnivores. Get the MMA if the serum number is ambiguous, and treat the number, not the symptom you were hoping it would explain.

Frequently Asked Questions

Is it safe to take a multivitamin every day if I eat healthy?

For most adults, yes, but it is usually unnecessary. The real risk is the fat-soluble and stored nutrients: vitamin A above 3,000 mcg RAE daily can cause liver damage and bone pain over time, and iron accumulates dangerously in people without menstrual losses, particularly men and postmenopausal women. Standard one-a-day products stay well below those ceilings, but stacked supplements or high-dose formulas can push you over.

What vitamins should a vegan take daily?

Vitamin B12 is the only non-negotiable one, at roughly 25-100 mcg daily or 2,500 mcg once a week, because no unfortified plant food contains it reliably. Add vitamin D if sun exposure is limited, and consider algae-based omega-3 (EPA and DHA) since flax provides ALA only. Iron and zinc are worth checking on a blood test rather than guessing, as plant forms are less absorbed.

Can I get all my vitamins from food alone?

Almost, with two exceptions. Vitamin D depends on sun exposure rather than diet; at UK latitudes above 50 degrees, skin synthesis is negligible from October to March, and the NHS advises a 10 mcg (400 IU) daily supplement in autumn and winter. Vitamin B12 is the other gap, affecting vegans, adults over 60 with reduced acid production, and anyone on long-term metformin or PPIs.

Do multivitamins help with fatigue if I eat well?

No. If your diet genuinely covers your needs, a multivitamin will not lift tiredness, and this is one of the most consistently negative findings in supplement research. Fatigue in well-nourished adults usually traces to poor sleep, iron deficiency without anaemia (ferritin under 30 ng/mL is worth treating), thyroid problems, or low mood. Get ferritin, TSH and B12 checked before spending money.

How much vitamin D should I take if I eat healthy?

Official guidance sits at 600 IU daily in the US and 400 IU (10 mcg) in the UK, but those are population minimums, not targets. Getting blood 25-hydroxyvitamin D measured is the only way to know; most adults sitting below 50 nmol/L need 1,000-2,000 IU daily to reach the 75 nmol/L range. Take it with a meal containing fat.

Are gummy multivitamins as good as tablets?

Usually not. Gummies are heat-processed, which degrades some B vitamins, and they often omit or underdose minerals like calcium and iron because those taste poor in a chewable base. ConsumerLab testing has repeatedly found gummies failing to meet label claims, and sugar or glucose syrup is typically the first ingredient. Choose a tablet or capsule with a USP, NSF or Informed Choice seal.