The short answer
Calcium is the one blocker that cuts both heme and non-heme iron. Keep dairy, calcium-rich foods and calcium supplements 3 to 4 hours away from iron meals and iron tablets. Butter and ghee are fine.
What counts as calcium
- All dairy except butter: milk, kefir, yogurt, cheese, cottage cheese and sour cream, including goat, sheep and lactose-free
- Whey protein powder
- Sesame seeds and tahini, almonds, chia and flax
- Firm tofu set with calcium, and fortified plant milks
- Whole sardines eaten with their bones
- Calcium tablets and some electrolyte powders
Make one meal your calcium meal, often breakfast, and keep it 3 to 4 hours from iron.
Add cheese, yogurt or a glass of milk to your iron meal.
- h3–4Between a calcium meal and iron
What is fine
- Butter and ghee, which carry almost no calcium
- Cashews, hazelnuts and Brazil nuts
- Coconut milk or cream instead of dairy cream
- Egg white protein instead of whey
If your doctor prescribed calcium, keep taking it. Ask about timing it 3 to 4 hours away from your iron.
Questions
Do I have to give up dairy?
No. Give it its own meal. Many people make breakfast their dairy meal and put iron into lunch and dinner.
Does calcium block meat iron too?
Yes. Unlike tea and coffee, calcium reduces heme iron absorption as well, which is why it needs the longest gap.
Sources
- 1.Hallberg L. et al. Calcium: effect of different amounts on nonheme- and heme-iron absorption in humans. American Journal of Clinical Nutrition, 1991
- 2.NIH Office of Dietary Supplements. Iron: fact sheet for health professionals
- 3.The Iron Guide, part 4: Food that counts
This page has not been reviewed by a clinician yet. Read it as general education, and take your own results to your doctor.
Educational, not medical advice. ferritin.ai does not diagnose or treat any condition, and it never sets a dose. Talk to your doctor about your own results.