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2Corrective

Iron

Also sold as Ferrous sulfate, bisglycinate, ferritin

For low ferritin, heavy periods, or pregnancy. Retest at three months and stop when replete.

2TrustedSupp Tier System™ · Tier 2Take until levels correct
Check before you startThis one has documented interactions with medication classes where the consequences are serious. If you take any prescription medicine, run it past a pharmacist before starting.

How long to take it

Temporary. Typically three to six months, then retest. Stop once ferritin is comfortably in range.

Who it's actually for

Only people with a confirmed low ferritin or a clear clinical reason. Never take iron speculatively.

Safe upper limit

Verified
45 mg per day (elemental)
The body has no way to excrete excess iron. Overload damages the liver, heart, and pancreas — and haemochromatosis is common enough to matter.
Iron — Consumer Fact SheetChecked Fri Aug 14 2026 00:00:00 GMT+0000 (Coordinated Universal Time)
40 mg for children 1–13, 45 mg for teens and adults 14+.

Interactions to know about

  • Thyroid medicationLevothyroxine, carbimazole, methimazole
  • AntibioticsEspecially tetracyclines and quinolones
  • Acid blockersOmeprazole, lansoprazole, famotidine
  • Parkinson's medicationLevodopa / carbidopa

Other supplements:

Run your full list through the interaction check.

Practical notes

  • Take with vitamin C; avoid tea, coffee, calcium and dairy within two hours.
  • Alternate-day dosing is often absorbed better and is gentler on the gut.
  • Bisglycinate causes less constipation than sulfate.