Deficiency/Women/Cognition

Iron

Essential mineral that restores iron stores, improves fatigue from deficiency, and helps adults with low ferritin or high iron needs.

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evidence

Caution

risk

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Use with caution

This supplement may interact with medications, medical conditions or sensitive populations. Review safety before use.

Overview

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Safety

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Quick Take

Use it if labs or clear risk factors point to low iron; otherwise skip routine self-supplementation.

Iron is an essential mineral found in red meat, shellfish, legumes, and fortified grains. It is required for hemoglobin, myoglobin, and enzymes that move oxygen and help make cellular energy. The best-supported uses are correcting iron deficiency anemia, lowering fatigue when ferritin is low, and maintaining iron status in pregnancy. People most likely to benefit are menstruating women, pregnant women, frequent blood donors, vegetarians, and anyone with confirmed low ferritin or low hemoglobin.

Potential benefits

Corrects iron-deficiency anemia

Prevents maternal anemia

Reduces fatigue when iron is low

Improves attention and memory

Improves restless legs symptoms

May reduce hair shedding

May support immune function

Protocol

Amount

25-65 mg elemental iron

Frequency

Once daily or every other day

When

Best on an empty stomach with water or vitamin C; if it causes nausea, take with a small meal and keep it away from calcium, coffee, tea, and antacids.

Onset Time

1-2 weeks for energy, 4-8 weeks for hemoglobin, 2-3 months+ for ferritin

Who Should Consider

Menstruating women with heavy periods

Vegetarians and vegans

Frequent blood donors

Adults with confirmed low ferritin

Pregnant women or trying to conceive

Long-term PPI or acid-blocker users

Food Sources

Clams (~24 mg per 85 g)
Beef (~2.6 mg per 100 g)
Lentils, cooked (~3 mg per 180 g)
Fortified breakfast cereal (~8-18 mg per serving)
Spinach, cooked (~6 mg per 180 g; lower absorption)
Tofu, firm (~3 mg per 120 g)

How It Works

Iron replenishes ferritin stores and provides the raw material for hemoglobin and myoglobin, improving oxygen transport to tissues. It also supports mitochondrial enzymes involved in ATP production, which is why low iron can show up as fatigue, poor concentration, and reduced work capacity.

Updated 5/19/2026