8 Nutrients Most Women Are Deficient In (and How to Fix It Through Food)

You’re standing in the vitamin aisle, and there are forty bottles all claiming to be the thing you’re missing. Women’s formula. Hair, skin, nails. Something with a leaf on it. You genuinely can’t tell if you need any of them, and nobody’s ever told you how you’d know.

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Here’s the thing — most of the nutrients women fall short on can be covered by about a dozen foods you already recognize. But before we get to those, we need to sort out a word that this whole topic gets wrong.

Jump to a sectionIn this article12 sections

1. First: Deficient, or Just Falling Short?
2. 1. Iron — The One That’s Actually Common
3. 2. Vitamin D — The Sunshine Problem
4. 3. Calcium — The Bone Bank
5. 4. Magnesium — The Quiet Gap
6. 5. Potassium — Under-Eaten, Under-Discussed
7. 6. Vitamin B12 — Depends Entirely on You
8. 7. Iodine — The Forgotten One
9. 8. Choline — The One You’ve Never Heard Of
10. Sorting Out What’s Real
11. Small Steps You Can Start This Week
12. The Bottom Line

First: Deficient, or Just Falling Short?

This distinction is the most useful thing in this article, so let’s get it straight.

A true deficiency means a blood test shows you’re low, and your body is showing signs — fatigue, weakness, real symptoms. This needs a doctor.

Falling short means you’re eating less of something than recommended, but your body is coping. You feel fine. There’s just room to do better over the long haul, especially for things like bones that quietly build or lose ground over decades.

Most of what gets called “deficiency” in women’s health content is actually the second one. That’s not nothing — it’s worth fixing. But it’s not an emergency, and it doesn’t mean you’re broken. 💡 Keep that filter on as you read the rest of this, including the parts I wrote.

1. Iron — The One That’s Actually Common

If you menstruate, you lose iron every month. That’s not a flaw in your diet; it’s just math. Iron deficiency is genuinely one of the most common nutritional deficiencies in women worldwide, and heavy periods are the biggest driver.

It’s also the one people most often miss, because the symptoms are so easy to explain away. Tired? Everyone’s tired. Winded on the stairs? Must be out of shape. In 20+ years of coaching, I’ve watched women grind through months of “I’m just not a morning person” that turned out to be low ferritin.

Food sources: red meat, shellfish, and poultry give you heme iron — the form your body absorbs most easily. Lentils, beans, tofu, pumpkin seeds, and spinach give you non-heme iron, which absorbs less readily. 💡 Pair the plant sources with vitamin C — beans with salsa, lentils with tomatoes, spinach with citrus — and absorption improves meaningfully.

Coffee and tea with meals do the opposite, so shift them between meals if iron is your issue.

⚠️ Do not take iron supplements on a hunch. Iron overload is a real condition, and excess iron isn’t harmless. Ask for a ferritin test. And note that after menopause, iron needs drop sharply — the same woman who needed iron at 35 may not at 55.

2. Vitamin D — The Sunshine Problem

Low vitamin D is widespread, and food is genuinely bad at fixing it. That’s not defeatism, it’s just true.

Your skin makes vitamin D from sunlight. If you work indoors, live somewhere with real winters, wear sunscreen (you should), or have darker skin, you make less. Meanwhile the food supply barely contains it. Fatty fish like salmon and sardines are the best natural source. Egg yolks have a little. Fortified milk and some mushrooms contribute a bit.

Vitamin D matters for calcium absorption and bone health — which is why it climbs the priority list heading into perimenopause and beyond. This is one of the few on this list where a supplement is often reasonable. Get tested, then talk to your doctor about what makes sense for you.

3. Calcium — The Bone Bank

Think of your bones as an account you deposit into for the first ~30 years and draw down after. Bone loss speeds up around menopause as estrogen falls. What you’re doing at 35 shows up at 65.

Food sources: dairy is the most efficient — yogurt, milk, cheese. If dairy isn’t for you: fortified plant milks (shake the carton, the calcium settles), canned sardines and salmon with the soft bones, tofu made with calcium, kale, bok choy, and almonds. Spinach is a trap here — it has calcium, but compounds in it block most of the absorption.

Ever wonder why calcium and vitamin D get sold together? Because you don’t absorb calcium well without D. They’re a team.

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4. Magnesium — The Quiet Gap

Most women eat less magnesium than recommended. But here’s the honest part: true magnesium deficiency is rare in otherwise healthy people. Your kidneys are good at holding onto it.

Magnesium is having a marketing moment — it’s blamed for and credited with everything from sleep to anxiety to cramps. Some of that has support, a lot of it is a stretch. I’d treat it as a worth-improving intake gap, not a crisis.

Food sources: pumpkin seeds, almonds, cashews, black beans, dark chocolate, spinach, and whole grains. If that list sounds like “eat more plants and nuts,” it’s because magnesium travels with fiber. Fix one, you tend to fix both.

5. Potassium — Under-Eaten, Under-Discussed

Potassium is one of the nutrients public health experts consistently flag as under-consumed, and almost nobody talks about it. It works opposite sodium and matters for blood pressure — which becomes a bigger deal for women after menopause, when heart risk rises.

Food sources: potatoes (yes, really — a plain potato beats a banana), beans, lentils, yogurt, salmon, avocado, tomatoes, oranges, and leafy greens.

6. Vitamin B12 — Depends Entirely on You

B12 comes almost exclusively from animal foods. So this one isn’t about women generally, it’s about specific situations:

• Vegetarians and especially vegans — you need fortified foods or a supplement, full stop
• Women over 50 — absorption declines with age, which is normal
• Anyone on metformin or long-term acid reducers — both can interfere with absorption

If none of those describe you and you eat meat, eggs, or dairy, you’re almost certainly fine.

Food sources: shellfish, beef, salmon, eggs, dairy, and fortified nutritional yeast or cereals.

7. Iodine — The Forgotten One

Iodine intake has drifted down over the years, partly because most of the salt in our food supply is not iodized — restaurant food, packaged food, and fancy sea salt generally aren’t. Iodine drives thyroid hormone, which drives your metabolism.

It matters most before and during pregnancy, when the need rises significantly for fetal brain development.

Food sources: iodized salt, dairy, eggs, cod, and seaweed. ⚠️ Go easy on seaweed and kelp — some varieties carry enormous amounts of iodine, and too much can disrupt the thyroid just like too little.

8. Choline — The One You’ve Never Heard Of

Most women don’t hit the recommended intake for choline, and most women have never heard the word. It matters for cell membranes, brain function, and especially fetal brain development in pregnancy.

Food sources: eggs are the standout by a wide margin — the yolk is where it lives. Also beef liver, chicken, fish, soybeans, and cruciferous vegetables.

Worth noting: the decades we spent afraid of egg yolks pushed people toward egg whites, which threw out the choline along with it. Current guidance is far more relaxed about eggs than the advice most of us grew up with.

Sorting Out What’s Real

Nutrient	Who’s actually at risk	Easiest food fix
Iron	Menstruating women, heavy periods, vegetarians	Red meat, shellfish; beans + vitamin C
Vitamin D	Almost everyone indoors, at northern latitudes, or with darker skin	Salmon, sardines — but food alone rarely does it
Calcium	Non-dairy eaters; everyone approaching menopause	Yogurt, fortified plant milk, sardines with bones
Magnesium	Most women fall short; true deficiency is rare	Pumpkin seeds, nuts, beans
Potassium	Most women fall short	Potatoes, beans, yogurt
B12	Vegans, women over 50, metformin/acid-reducer users	Shellfish, eggs, fortified foods
Iodine	Non-iodized-salt households; pregnancy	Iodized salt, dairy, cod
Choline	Most women fall short; matters most in pregnancy	Eggs — the whole egg

Small Steps You Can Start This Week

• Ask for a ferritin test at your next appointment if you’re tired and have heavy periods. This is the highest-value item on the page.
• Eat the whole egg. Choline, B12, iodine, a little vitamin D — one food, four nutrients.
• Put sardines or canned salmon in the rotation once a week. Calcium, vitamin D, iron, potassium, omega-3s. Nothing else on the list is this efficient.
• Keep pumpkin seeds in the cupboard. Magnesium and iron, no cooking required.
• Move your coffee 30–60 minutes away from meals if iron is your concern.
• Switch back to iodized salt for home cooking. It costs nothing.
• Add vitamin C to plant iron. Salsa, lemon, tomatoes, peppers.

Notice how short that list is. Eggs, sardines, seeds, beans, yogurt, and a potato cover most of this article. You do not need eight new habits.

The Bottom Line

The nutrients most women are deficient in aren’t a mystery, and the fix isn’t a cabinet full of bottles. It’s a handful of unglamorous foods showing up regularly, plus one blood test if you’ve been tired longer than you’d like to admit.

Perfect eating isn’t the goal and never was. A few reliable foods, most weeks, for years — that’s what actually builds the bone density and the iron stores and the energy you’ll want at 60. Small and consistent wins. It always has.

This article is for general information only and isn’t medical advice. Nutrient needs vary widely based on age, health conditions, medications, pregnancy, and diet. Talk with a healthcare professional or registered dietitian before starting any supplement or making significant dietary changes — and get tested before supplementing iron.

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Keep going: this article is part of my complete nutrition guide. For every guide, free tool, and honest review, organized by where you are stuck, visit the Start Here page.