Low Ferritin but Normal Haemoglobin — Should I Worry?

Can you be iron deficient without anaemia?

Absolutely. The body protects the haemoglobin to the last, draining the ferritin stores first. So there is a window — often months long — where ferritin is low, haemoglobin is still normal, and the standard "your blood count is fine" reassurance misses the problem entirely. Checking ferritin, not just haemoglobin, is what catches it.

What symptoms does low ferritin cause?

Even before anaemia, low iron stores can cause:

• Fatigue and reduced exercise tolerance
• Hair shedding — a very common and distressing early sign
• Restless legs, particularly at night
• Brittle nails, a sore tongue, and poor concentration

Many labs still flag ferritin as "normal" down to 15 µg/L, but symptoms of depletion commonly appear below about 30, and functional targets for issues like hair loss are often set higher still. Context — your symptoms — matters as much as the flag.

How do you raise ferritin, and how fast?

Dietary iron (red meat, pulses, leafy greens, fortified cereals) helps, but rebuilding depleted stores usually needs iron supplementation for three months or more — the haemoglobin corrects within weeks, but the ferritin stores take far longer to refill. Taking iron with vitamin C, and every other day rather than multiple times daily, improves absorption for many people.

When should you retest?

When to see a doctor

Low iron in a man, or a woman without heavy periods, always warrants a conversation about where the iron is going — occasionally the cause is slow blood loss from the gut that needs investigating.

Written by Dr Ibrar Ahmed — MBChB MRCP MRCGP PhD PG Dip (Cardiology)
Specialist interest: Cardiovascular Medicine · OneMedicine, CQC-registered clinic