Best vitamins for women by age: what you actually need in your teens, 20s, 30s, 40s and after 50

Short answer

Most women who eat a varied diet do not need a long list of supplements. A few, though, are clearly worth knowing about, and which ones depends on your age and situation (1):

• Folic acid, 400–800 micrograms a day, for anyone who could become pregnant. This is the one supplement with the strongest recommendation for women, because it lowers the risk of serious birth defects of the brain and spine (neural tube defects) (2).

• Iron, if you have heavy periods, are pregnant, eat little meat or have symptoms of low iron, but only after a ferritin test (3).

• Vitamin D, if you get little sun, have darker skin or live with long winters (4).

• Vitamin B12, if you are vegan, over about 50, or take metformin or acid-reducing medicines long term (5).

• Iodine and a prenatal vitamin during pregnancy and breastfeeding.

• Calcium, mainly from food, with attention after menopause.

A basic multivitamin with amounts close to recommended intakes should be safe for healthy people and can fill small gaps (1), but the US Preventive Services Task Force found insufficient evidence that it prevents heart disease or cancer in healthy people (6).

If you feel tired, foggy or "not yourself" and wonder whether you're missing something, you are not imagining it. Women are more likely than men to run low on iron, and symptoms are easy to dismiss. A few targeted tests beat a shelf of bottles.

Note: this article is for general education and is not medical advice. Supplement needs depend on your health, medicines and pregnancy plans. Talk to your doctor or pharmacist before starting supplements, especially iron, during pregnancy or if you take prescription medicines.

How much women need: recommended daily amounts by age

These are the US recommended intakes for women from food and supplements combined. They are targets, not supplement doses: most can be met from diet (3, 4, 7).

Two things stand out. Iron needs more than double during the years of periods compared with after menopause, and calcium needs rise again after 50. Those two shifts explain most of the differences between "vitamins for women in their 30s" and "vitamins for women over 50".

Vitamins for teen girls and teen boys

Teen vitamins are a growing category, often sold as gummies. For healthy teenagers who eat a reasonable diet, most nutrition experts do not recommend a routine multivitamin. The nutrients worth paying attention to are:

• Iron for teen girls. Once periods start, iron needs rise to 15 mg a day, and heavy periods, vegetarian diets, dieting and sports all raise the risk of deficiency (3). Tiredness, pale skin, breathlessness during sport and poor concentration are reasons to ask for a blood test.

• Calcium and vitamin D for both. The teenage years are when most bone mass is built, and calcium needs are higher at 14–18 than at any other age: 1,300 mg a day. Dairy, fortified plant milks, tofu and leafy greens are the main sources (7). Vitamin D supplements may be suggested for teens who get little sun.

• B12 for vegan teens, who need a reliable source from fortified foods or a supplement (5).

• Iron for teen boys, who need 11 mg a day during growth spurts; athletes on restrictive diets are most at risk.

Be cautious about products marketed for teen growth, height, muscle gain or "glowing skin". There is no supplement that increases height in healthy teens, and some sports products contain stimulants or undeclared ingredients. Keep iron supplements away from young children: iron overdose is a leading cause of fatal poisoning in children under six (3).

Vitamins for women in their 20s and 30s

The most important supplement: folic acid. The US Preventive Services Task Force gives a Grade A recommendation for 400–800 micrograms of folic acid a day for everyone who is planning or could become pregnant (2). It needs to be in place at least a month before conception and through the first months of pregnancy, when the baby's spine and brain form, and nearly half of pregnancies are unplanned. This is the main reason many women in their 20s and 30s take a multivitamin or prenatal vitamin.

Iron if your periods are heavy. Women aged 19–50 need 18 mg of iron a day, more than twice what men need. Heavy or long periods are the most common reason for iron deficiency in this age group (3). Signs include tiredness, breathlessness on stairs, hair shedding, cold hands and feet and a craving for ice. Ask for a ferritin test before taking iron.

Vitamin D if you get little sun. Office jobs, sunscreen, darker skin and northern winters all lower vitamin D. Testing is reasonable if you have risk factors; our guide to the vitamin D test explains the numbers.

B12 if you are vegan or take metformin, which is often prescribed for PCOS (5).

Pregnancy and breastfeeding change needs sharply: more folate, iron and iodine, and a prenatal vitamin is commonly recommended. Iodine is particularly important for the baby's brain development, and many prenatal vitamins contain it (8). Avoid high-dose vitamin A supplements in pregnancy, as too much preformed vitamin A can harm the baby.

Best vitamins for women in their 20s and best vitamins for women over 30 are popular searches, but the real list is short: folic acid if pregnancy is possible, iron if periods are heavy or a test shows low stores, and vitamin D and B12 if you are in a risk group.

Vitamins for women over 40

In the 40s, perimenopause brings changing periods, sleep and energy. Several nutrient questions come up:

• Iron can still matter, because periods in perimenopause are often heavier or more frequent before they stop. Heavy bleeding in this phase is worth discussing with a doctor in its own right.

• Vitamin D and calcium become more important as bone loss speeds up around menopause. Aim to meet calcium needs from food where possible.

• B12 absorption starts to decline with age and with long-term acid-reducing medicines.

• Magnesium is often taken for sleep and muscle tension; the evidence for these uses is modest, and it is worth a short, honest trial rather than a lifelong habit.

Tiredness, poor sleep, low mood and brain fog in your 40s are more often driven by perimenopause, stress and sleep than by a vitamin shortfall. Our articles on perimenopause symptoms or something else and on stress or perimenopause cover that overlap. If you are considering creatine, our article on creatine for women covers the evidence for muscle and bone.

Vitamins for women over 50 and over 60

After menopause, the picture changes in three ways:

1. Iron needs drop from 18 mg to 8 mg a day. Many "women's" multivitamins contain 18 mg of iron, which post-menopausal women generally do not need unless a test shows deficiency. Look for formulas designed for women over 50, which usually contain less or no iron (3). New iron deficiency after menopause should be investigated, as it can signal bleeding from the gut.

2. Calcium needs rise to 1,200 mg a day. Food is the preferred source. Calcium supplements are reasonable if diet falls short, but large doses of supplemental calcium have been linked to kidney stones, and some studies suggested a possible increase in heart attack risk; this is debated (7). Split supplements into doses of 500 mg or less, which are absorbed better.

3. B12 absorption falls, because stomach acid decreases with age. US dietary guidance suggests that adults over 50 get much of their B12 from fortified foods or supplements, which are absorbed more easily than B12 in food (5).

Vitamin D needs rise to 800 IU a day after 70, and deficiency is more common in older women who spend less time outdoors (4).

Do multivitamins help women over 60? In the large COSMOS trials, older adults who took a daily multivitamin had slightly better memory and global cognition over two to three years than those on placebo; the authors estimated the difference as about two years less cognitive ageing (9). That is a modest, encouraging result, not a reason to expect a multivitamin to prevent dementia.

Best multivitamin for women: do you need one?

A basic multivitamin at around 100% of daily values should be safe for healthy women and can cover small gaps in an imperfect diet (1). Combined with fortified foods and other supplements, though, it can push some nutrients past their upper limits. It makes the most sense if you:

• could become pregnant (for folic acid);

• eat a restricted diet, for example vegan, very low-calorie or with food allergies;

• have had weight-loss surgery;

• are over 50 and eat little, or have absorption problems.

It makes less sense to expect it to boost energy, prevent heart disease or cancer, or fix a real deficiency. Many multivitamins contain too little iron, vitamin D or B12 to correct a true deficiency, and the USPSTF found insufficient evidence for disease prevention in healthy adults (6).

What to look for when choosing a multivitamin for women:

• Folic acid around 400 mcg (more in prenatal formulas).

• Iron that matches your stage: around 18 mg before menopause, little or none after unless prescribed.

• Vitamin D and B12 at or above daily needs.

• No high doses of vitamin A (preformed retinol), especially if you could become pregnant.

• Vitamin B6 kept low, ideally under about 12 mg a day in total from all supplements.

• Independent quality testing by a third party, because supplements are not checked by regulators before sale.

• Gummy vitamins often contain sugar and may lack iron and some minerals; check the label if you rely on them.

What women should not take without a reason

• Beta-carotene and high-dose vitamin E: the USPSTF recommends against them for preventing heart disease or cancer; beta-carotene raises lung cancer risk in smokers (6).

• Iron without a test, especially after menopause.

• High-dose vitamin A in pregnancy or if you could become pregnant.

• High-dose vitamin B6, common in "hormone balance" and PMS products, which can damage nerves.

• High-dose biotin before blood tests, because it can distort thyroid and other results.

• "Hormone balance" blends with many herbs, which have little evidence and can interact with medicines, including contraceptives.

Living with "which vitamins do I need?": the questions people ask next

What vitamins should a woman take daily?

There is no single list for every woman. Folic acid (400–800 mcg) is recommended daily for anyone who could become pregnant. Iron, vitamin D and B12 are worth taking if a test shows you are low or you are in a risk group: heavy periods for iron, little sun for vitamin D, vegan diet or age over 50 for B12. A standard multivitamin can cover small gaps but is not required if you eat a varied diet.

Should women take iron every day?

Only if a test shows you need it, or your doctor recommends it, for example during pregnancy. Women with heavy periods are at higher risk of low iron, so ask for a ferritin test if you feel tired, breathless or notice hair shedding. Taking iron without a need can cause constipation and stomach upset, and after menopause new iron deficiency should be investigated rather than simply treated.

Is a prenatal vitamin better than a regular multivitamin?

If you are pregnant, breastfeeding or trying to conceive, yes: prenatal vitamins usually contain more folic acid, iron and iodine, and they keep vitamin A at safe levels. If you are not planning a pregnancy, a regular multivitamin is usually enough, and the extra iron in prenatal vitamins may not be needed. Ask your doctor or midwife which is right for you.

Do teenage girls need iron supplements?

Not routinely. But teenage girls need more iron than boys once periods start, and heavy periods, vegetarian diets, dieting and sports raise the risk of deficiency. If a teenage girl is tired, pale, breathless during sport or struggling to concentrate, a blood test including ferritin is a sensible step before starting iron.

What is the best vitamin for women over 50?

Vitamin D and B12 are the two most commonly needed after 50, along with enough calcium, ideally from food. Iron needs drop after menopause, so many women over 50 do not need iron in their multivitamin. A daily multivitamin may modestly support memory in older adults, according to the COSMOS trials. A doctor can check vitamin D and B12 levels if you are unsure.

Are gummy vitamins as good as tablets?

Gummies can provide the same vitamins, but they often contain sugar and may lack iron and some minerals. They are easy to overeat, which is a particular concern with iron and for children in the house. If you prefer gummies, check the label for what is missing and keep them out of children's reach.

Before you blame yourself

Women often carry the idea that feeling tired, foggy or flat is just part of life, or a sign they are not coping. But women's bodies change their needs across decades, from heavier periods in the teens and 40s to lower iron needs and higher calcium needs after menopause. Feeling different at different ages is not failure; it is biology changing underneath you.

The useful step is not to buy every "women's formula" on the shelf. It is to know the few nutrients that matter for your stage, get the right tests, and fix what is actually low.

When to see a doctor

See a doctor if you have tiredness that lasts more than a few weeks, very heavy or long periods, breathlessness, hair loss, or if you are planning a pregnancy. After menopause, see a doctor about any new iron deficiency or any vaginal bleeding.

Call 911 or seek urgent care for chest pain, fainting or breathlessness at rest. If a child may have swallowed iron tablets, call Poison Control (1-800-222-1222) or 911 right away (10).

How to bring this up with your doctor

What to ask for, by name. "Could we check a full blood count, ferritin, vitamin D and B12?" If you are planning a pregnancy: "Should I start folic acid now, and is my dose right for me?" After 50: "Do I still need iron in my multivitamin?"

What to bring. Every supplement you take with its doses, a note of your periods (how heavy, how long), your diet pattern, medicines such as metformin or acid-reducing tablets, and your pregnancy plans.

What to say, out loud. "I'd like to take only what I actually need. Based on my age, periods and diet, which supplements make sense for me, and which tests would tell us?"

If you are told you're fine without tests. Ask: "Given my heavy periods / vegan diet / age, would a ferritin, B12 or vitamin D test be worthwhile?"

How long until you notice a difference? Most supplements take weeks, not days. See how long supplements take to work, and how to tell if one is working.

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How Welltory helps — and what it cannot do

The limits first. Welltory is a general wellness product, not a medical device. It cannot measure iron, vitamin D, B12 or any nutrient, and it does not diagnose deficiencies or any other condition. Blood tests are the only way to know your levels.

What it can do is help you see how you are actually doing day to day, and whether a change you make, such as starting iron after a low ferritin result, is followed by a difference.

Sleep and morning energy. Sleep Analysis uses Apple Watch or Oura data on iOS and syncs sleep from Samsung Health, Fitbit or Garmin Connect through Health Connect on Android (Sleep Analysis for Android). On the Today screen (iPhone with Apple Watch or Oura), Battery starts each morning from your resting heart rate on waking and the quality of your sleep (Today screen).

Tag what matters for women. Welltory does not predict or analyse your cycle, but Journal can show menstrual cycles you add or sync from apps like Apple Health, and you can note it in tags. On the Today screen (iOS, with Apple Watch or Oura), when Welltory marks a stress or rest episode and asks "What happened?", tap, type or talk: "period day 1", "heavy day", "started iron", "started prenatal", "hot flush". Over weeks, My Patterns shows which tags tend to appear with stress and which with recovery; some sections need a paid plan.

Before and after a change. If you start a supplement after a test, compare four to eight weeks before and after: sleep, Battery, resting heart rate and, if you measure it, morning HRV taken at the same time after waking, before coffee (accurate HRV measurements).

A record for your doctor. From the web app you can export a CSV (Dashboard → choose a chart → Export) (export guide). Patterns are associations to discuss with your doctor, not proof that a supplement worked.

How we made it

We based this article on NIH Office of Dietary Supplements fact sheets for multivitamins, iron, vitamin D, vitamin B12, calcium and iodine, the US Preventive Services Task Force recommendations on folic acid (2023) and on vitamin supplements for preventing heart disease and cancer (2022), and the COSMOS multivitamin trials. Search questions came from what people in the United States most often ask about vitamins for women and teens. For the product section, we checked every function against the Welltory Help Center on October 21, 2026.

Made with AI tools, then edited and fact-checked by the Welltory team. See our Editorial & AI policy.

Jane Smorodnikova, co-founder of Welltory, built the methodology behind how we read physiological data.

Written by Tatsiana Yashyna.

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