40XP
In women with unexplained fatigue and low-to-borderline iron stores, iron supplementation reduced fatigue more than placebo over four weeks — but the benefit was limited to those with low ferritin.
Iron
A mineral the body needs to make haemoglobin; supplementing mainly helps when levels are actually low.
Often taken withVitamin C
Evidence-backed benefits
How Iron can help, goal by goal, with the studies behind each score.
How to read XP
Each score is for this supplement and that specific goal, not a general rating.
XP combines how reliable the research is with how much difference it usually makes. Higher means stronger evidence for that supplement and that goal.
Limited<15 XPModest15–27 XPModerate28–44 XPReliable45–69 XPHigh70+ XP
Dosage
What studies commonly use for Iron, and how it is usually taken.
Usual dose
60–120 mg per day
60-120 mg/day of elemental iron (only once a blood test shows low ferritin)
How to take it
- With food
See study range
up to 325 mg/day of ferrous sulfate (about 65 mg elemental iron) under medical supervision
Your journey
Daily Energy & Fatigue comes first (week 2 → week 8); Daily Energy & Fatigue takes longest (week 2 → week 8). An estimate from the studies' timelines, not a promise: everyone responds differently.
From the first noticeable effect to roughly full strength. Colour follows the XP tier of each benefit.
Make it a habit
These gains come from steady use, not a single dose. Keep Iron in your routine for about week 8 before you judge it.
Safety
What to know before you take Iron.
Safety rating
Use with care
Dose and timing matter.
- Doesn't help if your iron is already fineGet a blood test first — taking iron when your levels are normal won't fix fatigue and can cause side effects.
- Stomach upset is commonNausea, constipation, cramping and dark stools are common — taking it with food (at some cost to absorption) or every other day can help.
Check with a doctor first if you haven't had a blood test confirming low iron or ferritin, you have a condition like hemochromatosis, or you're pregnant — get tested before you supplement.
General information, not medical advice. If you are pregnant, take medication or have a health condition, check with a doctor or pharmacist first.
Common pairings
Supplements and habits often combined with Iron.
Vitamin C
Vitamin C improves how much iron your body absorbs from a supplement.
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