How much iron do pregnant women need?

The iron RDA during pregnancy is 27 mg per day — the highest adult target — to support blood volume expansion, the placenta, and fetal iron stores. Most pregnant people need a prenatal supplement because diet alone rarely reaches 27 mg.

What foods are high in iron?

Heme iron sources include beef, liver, oysters, and dark poultry meat. Non-heme sources include lentils, spinach, tofu, fortified cereal, pumpkin seeds, and beans. Vitamin C with meals boosts non-heme absorption; tea and coffee can reduce it if drunk with iron-rich meals.

Iron Intake Calculator

Find how much iron you need per day based on NIH RDA values for your age, sex, pregnancy status, and diet — including vegetarian adjustments.

Most adult men need 8 mg of iron/day. Women 19–50 need 18 mg. Pregnancy jumps to 27 mg. Vegetarians should multiply by 1.8.

Based on NIH Office of Dietary Supplements / Institute of Medicine RDAs. For educational use — not a medical diagnosis.

Sex

Male Female

Age Diet Today’s iron intake (optional, mg) Compare what you’ve eaten so far with your daily target

Pregnant Lactating / breastfeeding

How to Use This Iron Intake Calculator

Select your sex, enter your age, mark pregnancy or lactation if it applies, and choose omnivore or vegetarian/vegan. This iron intake calculator maps you to the NIH Recommended Dietary Allowance (RDA), applies the vegetarian ×1.8 factor when needed, and optionally compares today’s intake with your target.

Iron deficiency is the world’s most common nutritional deficiency. Many women of reproductive age, pregnant people, toddlers, and plant-based eaters fall short — often without obvious symptoms until fatigue or anemia shows up on labs.

How Much Iron Do You Need Per Day?

Your daily iron requirement depends on age, sex, and life stage — not body weight. Menstruation roughly doubles women’s needs versus men; pregnancy nearly triples the adult male RDA because blood volume expands ~50% and the fetus builds iron stores for the first months of life.

Group	Iron RDA	Vegetarian (×1.8)
Men 19+	8 mg	14 mg
Women 19–50	18 mg	32 mg
Women 51+	8 mg	14 mg
Pregnancy (14–50)	27 mg	49 mg
Lactation 19–50	9 mg	16 mg
Lactation 14–18	10 mg	18 mg
Teen boys 14–18	11 mg	20 mg
Teen girls 14–18	15 mg	27 mg
Children 9–13	8 mg	14 mg
Children 4–8	10 mg	18 mg
Children 1–3	7 mg	13 mg
Infants 7–12 months	11 mg	20 mg

Source: NIH Office of Dietary Supplements / Institute of Medicine. Adult Tolerable Upper Intake Level (UL) is 45 mg/day from food + supplements (ages 14+), unless a clinician advises otherwise.

How This Iron Intake Calculator Works

The math is a lookup plus one optional multiplier — no TDEE formula required:

Step 1: Match age, sex, and pregnancy/lactation status to the NIH iron RDA table.
Step 2: If you eat vegetarian or vegan, multiply that RDA by 1.8 (IOM bioavailability adjustment for non-heme iron).
Step 3: Optionally enter today’s estimated iron intake to see percent of target and milligrams remaining.

Example: Woman, age 28, omnivore

RDA = 18 mg/day. A bowl of fortified cereal (~18 mg) can cover the whole day; more realistically, mix beef, beans, and greens across meals.

Example: Vegetarian woman, age 28

Base RDA 18 mg × 1.8 = 32 mg/day. Prioritize fortified cereal, lentils, tofu, and vitamin C with every iron-rich meal.

What Is Iron, and Why Does It Matter?

Iron is a mineral your body needs to make hemoglobin (oxygen transport in red blood cells), myoglobin (oxygen storage in muscle), and dozens of enzymes involved in energy metabolism and immune function. Without enough iron, tissues get less oxygen — which shows up as fatigue, reduced exercise capacity, brain fog, and, in more severe cases, iron-deficiency anemia.

Your body carefully recycles iron from old red blood cells, so daily dietary needs look “small” in milligrams. Losses still add up from menstruation, pregnancy, growth, blood donation, GI bleeding, and intense endurance training.

Heme vs Non-Heme Iron

Not all dietary iron is absorbed equally. Understanding the two forms is the key to hitting your target:

Property	Heme iron	Non-heme iron
Sources	Meat, poultry, seafood	Plants, fortified foods, eggs, dairy
Typical absorption	~15–35%	~2–20%
Boosted by vitamin C?	Less dependent	Yes — strongly
Inhibited by tea/coffee?	Mildly	Yes — polyphenols reduce uptake
Best for	Efficient top-ups	Plant-based diets (need higher totals)

That’s why this iron intake calculator multiplies vegetarian targets by 1.8. You’re not “missing” iron chemically — you’re accounting for lower average absorption.

High-Iron Foods (Practical Portions)

Use food labels when you can; these USDA/NIH-style estimates help you plan meals that hit your RDA:

Food	Serving	Iron (approx.)	Type
Fortified breakfast cereal	1 serving	~18 mg	Non-heme
Oysters, cooked	3 oz	~8 mg	Heme
White beans, canned	1 cup	~8 mg	Non-heme
Dark chocolate (45–69% cacao)	3 oz	~7 mg	Non-heme
Beef liver	3 oz	~5 mg	Heme
Lentils, cooked	½ cup	~3 mg	Non-heme
Spinach, cooked	½ cup	~3 mg	Non-heme
Tofu, firm	½ cup	~3 mg	Non-heme
Chickpeas, cooked	½ cup	~2–3 mg	Non-heme
Pumpkin seeds	1 oz	~2.5 mg	Non-heme
Lean ground beef	3 oz	~2 mg	Heme
Chicken thigh, cooked	3 oz	~1 mg	Heme

Smart pairings: lentils + tomatoes, tofu + bell peppers, beans + salsa, spinach salad + orange slices. Delay tea and coffee until 1–2 hours after an iron-focused meal when possible.

Iron Needs in Pregnancy

The pregnancy RDA of 27 mg/day is the highest adult target. Maternal blood volume rises, the placenta develops, and the fetus stores iron for the first ~6 months after birth. Median dietary iron intake in pregnant women is often closer to 15 mg/day — well below the RDA — which is why prenatal vitamins with iron are standard in many guidelines (ACOG commonly discusses ~30 mg elemental iron in prenatals; WHO recommends iron/folate supplementation programs in many settings).

Do not invent high-dose iron on your own. Excess iron can cause nausea and constipation, and dosing should follow your clinician and labs. Use our pregnancy macro calculator alongside this tool for calorie and protein planning.

Iron for Vegetarians and Vegans

Plant-based diets can meet iron needs, but they need more planning. The IOM’s ×1.8 adjustment means an adult woman targeting 18 mg as an omnivore aims for about 32 mg as a vegetarian. Practical levers:

Eat iron-fortified cereal or nutritional yeast products daily when available
Include legumes (lentils, chickpeas, beans) most days
Add vitamin C to every iron-rich meal
Cook in cast iron when practical (small boost for acidic foods)
Separate tea/coffee from main iron meals
Get ferritin checked if fatigue persists despite a solid diet

Who Is at Higher Risk of Low Iron?

You may need closer tracking (and sometimes labs) if you fall into one of these groups:

Women with heavy menstrual bleeding
Pregnant or recently postpartum people
Infants, toddlers, and teens in growth spurts
Frequent blood donors
People with celiac disease, IBD, or gastric bypass / absorption issues
Vegetarians and vegans without planned iron sources
Endurance athletes (foot-strike hemolysis + higher needs)
People with low calorie diets that crowd out iron-dense foods

Signs You Might Be Low on Iron

Symptoms are nonspecific: fatigue, weakness, pale skin, shortness of breath on exertion, cold hands/feet, brittle nails, restless legs, hair shedding, or reduced training performance. Only blood tests (typically ferritin, hemoglobin, and related CBC markers) confirm deficiency. This calculator sets a dietary target — it does not diagnose anemia.

Can You Get Too Much Iron?

Yes. The adult UL is 45 mg/day from food and supplements combined for most people ages 14+. High-dose supplements without confirmed deficiency can cause GI distress and are dangerous for people with hereditary hemochromatosis. Accidental iron overdose is also a serious risk for young children — keep supplements locked away.

Food iron alone rarely exceeds the UL. Problems usually come from stacking multivitamins, prenatal vitamins, and extra iron pills.

How to Increase Iron Intake Safely

Start with food: add one iron-dense item to breakfast and one to dinner before jumping to supplements.
Pair with vitamin C: citrus, strawberries, kiwi, peppers, tomatoes, or broccoli with the meal.
Time inhibitors: move tea, coffee, and large calcium supplements away from iron-focused meals.
Track for a week: labels + a simple log beat guessing — then compare with this iron intake calculator.
Test, don’t guess: if symptoms persist, ask for ferritin before high-dose self-supplementation.
Build balanced plates: iron works best inside an overall adequate diet — see our protein intake calculator and fiber calculator.

Medical disclaimer: This iron intake calculator provides general dietary guidance based on NIH RDAs and is not a substitute for medical advice, diagnosis, or treatment. Iron needs change with illness, surgery, malabsorption, and genetics. Consult a healthcare professional before starting iron supplements, especially if you are pregnant, have a chronic condition, or a family history of hemochromatosis.

How this calculator works

We map your age, sex, and pregnancy/lactation status to the NIH iron RDA table, optionally apply the vegetarian ×1.8 factor, compare an optional intake entry with your target, and show the 45 mg adult UL for context.

Frequently asked questions

How much iron do I need per day?+

Adult men and women 51+ need about 8 mg/day. Women 19–50 need 18 mg because of menstrual losses. Pregnancy requires 27 mg. Teen boys need 11 mg and teen girls 15 mg. Use the calculator above for your exact NIH RDA group and vegetarian adjustment.

Do vegetarians need more iron?+

Yes. The Institute of Medicine recommends multiplying the iron RDA by 1.8 for vegetarians because non-heme plant iron is absorbed less efficiently than heme iron from meat. Focus on legumes, fortified cereal, tofu, seeds, and vitamin C with meals.

How much iron during pregnancy?+

27 mg/day is the RDA. Most prenatal vitamins include iron because food alone rarely covers this target. Follow your clinician’s supplement advice and lab monitoring rather than stacking extra high-dose iron on your own.

What foods are highest in iron?+

Fortified cereal can provide a full day’s iron in one serving. Other strong options: oysters, white beans, liver, lentils, spinach, tofu, pumpkin seeds, and lean beef. Combine plant sources with vitamin C for better absorption.

Can I take too much iron?+

The adult UL is 45 mg/day from food and supplements combined. High-dose iron without confirmed deficiency can cause side effects and is risky with hemochromatosis. Keep iron supplements away from children.

What are symptoms of low iron?+

Common signs include fatigue, weakness, pale skin, shortness of breath, cold extremities, brittle nails, and reduced exercise performance. Only blood tests such as ferritin and hemoglobin confirm deficiency — use this calculator for dietary targets, not diagnosis.

Does vitamin C help iron absorption?+

Yes for non-heme (plant) iron. Ascorbic acid converts iron into a more absorbable form and can substantially raise uptake from the same meal. Add citrus, peppers, tomatoes, or berries alongside beans, greens, or fortified grains.

Should I take an iron supplement?+

Only when diet and clinical need justify it. Many pregnant people take iron via prenatals. Outside pregnancy, get labs first — unnecessary supplements can cause constipation and, in some people, iron overload. Ask a clinician for dose and timing.