Iron is the supplement people quit fastest, and usually for the same reason: the standard prescription is a large daily dose of a harsh form, taken wrong.
Who actually needs it
Low ferritin shows up as fatigue that sleep does not fix, breathlessness on stairs, cold hands, and flat training. It is most common in people who rarely eat red meat, endurance athletes, and menstruating women. If that is not you, do not supplement iron blind - excess iron is genuinely unhelpful.
Making it absorb
- Go every other day. A daily dose raises hepcidin, the hormone that blocks the next dose. Alternate-day dosing absorbs comparably with half the gut complaints.
- Pair with vitamin C, not coffee. Ascorbate roughly doubles non-heme absorption; coffee and tea within an hour of the dose cut it sharply.
- Separate from calcium and zinc. They compete for the same transporter.
- Choose bisglycinate. Gentler on the stomach than ferrous sulfate at equivalent elemental doses.
Check, then adjust
Re-test ferritin after about three months. Restoring depleted stores takes a full season, not a fortnight - set expectations accordingly. Your diet answers and symptoms give the first estimate of whether iron belongs in your formula at all; the quiz does exactly that weighting.
