Wellness . Symptoms guide
Iron Deficiency Symptoms and Testing
Iron deficiency is the most common nutritional deficiency in the UK. Symptoms often appear before standard anaemia tests turn abnormal. A full iron study (ferritin, serum iron, total iron binding capacity, transferrin saturation) gives a much clearer picture than ferritin alone or full blood count alone.
This patient information is being clinically reviewed by our team. The factual content draws on UK guidance (NHS, NICE, British Association of Dermatologists, British Society for Sexual Medicine where cited).
What this might be
- Dietary insufficiency. Especially in vegan or vegetarian patients.
- Heavy menstrual bleeding. Common in women of reproductive age.
- Increased demand. Pregnancy, breastfeeding, endurance training.
- Malabsorption. Coeliac disease, gastric surgery.
- Occult GI bleeding. Always considered in men and postmenopausal women.
When to seek urgent advice
If any of the following apply, please contact your GP, NHS 111, or A&E in the first instance rather than waiting for private bloodwork.
- Black, tarry stools
- Visible blood in stool
- Iron deficiency in a man or postmenopausal woman without obvious cause (warrants GP investigation)
Common features that suggest this
- Fatigue, especially with exertion
- Hair shedding
- Brittle nails
- Breathlessness on stairs
- Restless legs
- Pica (craving ice or unusual substances)
Recommended tests
Same-day appointments at our Harley Street clinic, results clinician-reviewed.
Need a marker not in these panels? Build a custom panel and a GMC-registered clinician will design one for you.
Testing advice
No fasting. Avoid iron supplements for at least 24 hours before testing if you want a true baseline.
Common questions
What is a healthy ferritin level?
NHS lower limits are around 15 to 30 micrograms per litre, but for hair growth and fatigue, many clinicians aim for above 70 micrograms per litre. Context matters.
Can I just take iron supplements?
Supplements help correct deficiency but do not address the cause. Persistent unexplained iron loss needs investigation, especially in men and postmenopausal women.
Related symptoms
Sources and further reading
This page provides general information only and is not a substitute for medical advice. A GMC-registered clinician will review your results and tailor any recommendations to you personally.