The short answer
Yes. Coffee's polyphenols grab plant and supplement iron in your gut, and a cup with a meal can sharply cut what you absorb from it. Have coffee 1 hour before or 2 hours after a plant-iron meal or an iron supplement. Iron from meat and fish is barely affected.
Have coffee 1 hour before, or 2 hours after, a plant-iron meal or your supplement.
Wash down a bean, grain or egg meal with coffee.
Why it happens
Coffee, like tea, cocoa and red wine, carries polyphenols, often called tannins. In your gut they bind to non-heme iron, the kind in plants, eggs and supplements, and carry it out unabsorbed. Heme iron from meat and fish takes a different route and barely notices.
Keeping your morning coffee
- Take your iron supplement at bedtime, far from the morning cup.
- Make breakfast your dairy meal or a heme meal, rather than your plant-iron meal.
- Put plant iron into lunch and dinner, with coffee at least an hour before.
- Before is safer than after, since digestion speed varies.
With very low ferritin, the guide keeps coffee away from every iron meal at first, heme ones included, until stores start to move.
A real page from The Iron GuideA day of iron timing, from the guide's food chapter.See more pagesQuestions
Does decaf block iron too?
Yes. The polyphenols do the blocking, not the caffeine, so decaf counts as coffee.
Can I drink coffee with a steak?
Yes. Heme iron is barely affected, so coffee after a steak or liver pâté is fine. Beans or eggs on the same plate are another matter.
Does milk in my coffee matter?
Milk adds calcium, which blocks both kinds of iron. Keep a milky coffee away from iron meals too.
Sources
- 1.Morck T.A., Lynch S.R., Cook J.D. Inhibition of food iron absorption by coffee. American Journal of Clinical Nutrition, 1983
- 2.Hurrell R.F., Reddy M., Cook J.D. Inhibition of non-haem iron absorption in man by polyphenolic-containing beverages. British Journal of Nutrition, 1999
- 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.