Iron Panel
A single iron test doesn't tell the full story. The complete panel — serum iron, TIBC, transferrin saturation, and ferritin — shows whether you're truly deficient, overloaded, or just fine.
Your iron panel measures how much iron is in your blood, how much capacity your blood has to carry more, and how much you have stored. Together, these four markers distinguish iron deficiency, iron overload, chronic disease, and normal iron status.
What is this test?
The iron panel is a group of four blood tests that together give you the full picture of your iron status. Checking just one — like serum iron or hemoglobin — is like reading one page of a book. Here's what each component tells you:
- Serum iron — iron circulating in your blood right now (fluctuates throughout the day)
- TIBC (Total Iron Binding Capacity) — how much room your blood has to carry more iron. High TIBC means your body wants more iron
- Transferrin saturation — the percentage of iron-carrying capacity that's actually being used. The most useful single number
- Ferritin — your iron stores. How much iron your body has saved up for future use
What your numbers mean
| Marker | Standard range | Optimal |
|---|---|---|
| Serum Iron | 60–170 µg/dL | 80–150 µg/dL |
| TIBC | 250–370 µg/dL | 280–350 µg/dL |
| Transferrin Sat | 20–50% | 25–45% |
| Ferritin (men) | 30–400 ng/mL | 40–150 ng/mL |
| Ferritin (women) | 15–150 ng/mL | 40–100 ng/mL |
Ferritin below 30 ng/mL with normal hemoglobin is extremely common — especially in women, vegetarians, and athletes. You'll feel tired, but your doctor may say your blood work is "normal." Ask for ferritin specifically.
How to improve your iron status
- If deficient — iron bisglycinate is the best-tolerated supplement. Take on an empty stomach with vitamin C for better absorption
- Avoid tea/coffee with meals — tannins and polyphenols block iron absorption by up to 60%
- Space iron from calcium — calcium competes with iron for absorption. Take them at different times
- Eat iron-rich foods — heme iron (meat, fish) absorbs best. Non-heme (spinach, lentils, jaggery) absorbs better with vitamin C
- If overloaded — stop iron supplements, avoid vitamin C with meals, consider therapeutic phlebotomy (blood donation)
- Retest in 3 months — ferritin changes slowly. Give supplementation time to work before retesting
Track your iron panel over time
eterni connects ferritin, transferrin saturation, and hemoglobin into one trajectory — so you know if your supplement is actually working.
Get early accessFrequently Asked Questions
What's the difference between serum iron and ferritin?
Serum iron measures iron currently circulating in your blood — it fluctuates throughout the day and after meals. Ferritin measures your iron stores — how much iron your body has saved up. You can have normal serum iron but low ferritin, meaning you're running on empty. Ferritin is the better long-term indicator.
Can I have normal hemoglobin but low iron?
Yes — this is called iron deficiency without anemia and it is extremely common. Your body prioritises hemoglobin production, so ferritin drops long before hemoglobin does. You can have fatigue, brain fog, hair loss, and exercise intolerance with perfect hemoglobin but ferritin below 30 ng/mL.
When should I take iron supplements?
Only if your ferritin is low (below 30 ng/mL) or you have documented iron deficiency anemia. Iron bisglycinate is the best-tolerated form. Take it on an empty stomach with vitamin C for better absorption, and away from tea, coffee, and calcium. Do not supplement iron without testing — excess iron is harmful.
Is iron overload a concern?
Yes, especially for men and postmenopausal women who do not lose iron through menstruation. Ferritin above 300 ng/mL in men or above 200 ng/mL in women warrants investigation. Hereditary hemochromatosis affects about 1 in 200 people of European descent. Excess iron causes oxidative damage to the liver, heart, and pancreas.
Reading the pattern
| Pattern | Serum Iron | TIBC | Sat% | Ferritin |
|---|---|---|---|---|
| Iron deficiency | Low | High | Low | Low |
| Chronic disease | Low | Low–Normal | Low–Normal | Normal–High |
| Iron overload | High | Low | High | High |
| Normal | Normal | Normal | 25–45% | 40–150 |
India-specific context
- Anemia prevalence — over 50% of Indian women and 25% of Indian men are anemic, with iron deficiency being the leading cause
- Vegetarian diets — non-heme iron from plant sources has 2–20% absorption vs 15–35% for heme iron from meat. Vegetarians need to be more intentional about iron intake
- Tea with meals — drinking chai with or immediately after meals is very common in India and significantly reduces iron absorption
- Ferritin as acute phase reactant — ferritin rises with inflammation, infection, and liver disease. An elevated ferritin doesn't always mean iron overload — check CRP alongside it
Know what's working. Know what's not.
eterni connects your lab results, supplements, and retests — so you can see the trajectory, not just a snapshot.
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