Iron & Ferritin: Test first.
5 sections, about 8 minutes in total
18 mg
The daily reference intake for menstruating women is 18 mg, vs 8 mg after menopause (NIH).
Ferritin
Ferritin is the blood test that measures your iron stores.
Never
Never supplement iron without a test. Testing always comes first.
Start with the signs
The signs of low iron.
Low iron reduces how much oxygen your blood carries, and that shows up as everyday exhaustion. Tap the signs you have to see why they happen.
Nothing you tap is stored. This is a mirror for you, not a form for us.
What the evidence says
When iron helps.
Iron supplements reduce fatigue in women whose iron is low on a blood test. If your iron is normal, extra iron does not add energy. It can cause stomach problems and build up in the body.
Tap a promise from the label or the ad:
Pick a claim, make your call, then see what the trials actually found.
Verdicts summarize the cited research and will change if the research changes. Iron itself stays test-first, with the dose decided from the test.
Why levels drop
Why women run low.
Periods lose iron every month, and diet often does not replace it. Ferritin falls first, long before anemia shows. Click through to see how the deficit builds.
Tap a step to open it. Each one carries the detail.
The ferritin detail that matters
Ferritin measures your iron stores. It drops before hemoglobin does, so a test can show no anemia while your stores are low. If you have the symptoms above and a test says no anemia, ask what your ferritin value was.
Why testing comes first
Do not self-prescribe iron.
Taking iron without a test has three problems. It can build up in the body. It can hide the reason you are losing iron. It often causes stomach problems.
What iron without a test risks
- Overload is the first risk. The body has no good way to excrete excess iron, and some people (with hereditary hemochromatosis) accumulate it dangerously without knowing until damage is done
- Masking is the second and most dangerous risk. Iron can relieve the symptom while the actual cause (heavy bleeding, gut loss, an absorption disease) goes uninvestigated
- Gut trouble is the third risk. Constipation, nausea and black stools are common, and the wrong dose or form makes deficient women quit the treatment they needed
What the tested path looks like
- A ferritin test plus a full blood count at a routine blood draw, which is cheap, standard and definitive
- If you are low, your doctor picks the dose, form and schedule, investigates why you are low (which is the most important part), and rechecks until your stores refill
- If you are fine, you have avoided months of unnecessary pills, and the food habits below still apply
Heavy periods deserve their own appointment regardless. ACOG is clear that soaking through protection every hour is a medical conversation in its own right, and it should not be managed with iron alone.
The habits that help
Food is the part you control.
Food habits help, but a ferritin test matters more than any of them. Tap a habit to see what it does.
Tap a tab to open it. The detail lands here.
If iron is prescribed, take it as scheduled and expect a recheck. Report black stools or stomach side effects instead of stopping without saying.