The short answer
Start with an iron food and add something raw with vitamin C. On a plant plate, add a little meat or fish, or choose soaked beans and sourdough. Then keep dairy 3 to 4 hours away, and coffee and tea, herbal teas too, 1 hour before or 2 hours after.
- 1An iron food. Meat, fish, liver or mussels, or beans, lentils, tofu and seeds. See iron-rich foods.
- 2Something raw with vitamin C. Red pepper, parsley, kiwi, lemon or blackcurrants. It turns plant iron into the form your gut takes up. See vitamin C and iron.
- 3Help for plant iron. A little meat or fish, soaked beans, sprouted lentils or long-fermented sourdough.
- 4What waits. Dairy 3 to 4 hours away. Coffee and tea, herbal teas too, 1 hour before or 2 hours after. Matcha 3 to 4 hours each side. See what blocks iron.
What helps, and how sure the studies are
| Helper | What it did in studies | How sure |
|---|---|---|
| Vitamin C | 25 mg in a meal raised its iron absorption 1.65 times | Strong |
| A little meat or fish | 50 g of pork raised plant-iron absorption from a rice, pea and bread meal by 44% | Strong |
| Breaking down phytate | Iron absorbed from wheat porridge went from 1% to 11.5% | Depends on the food |
| Colour (carotenoids) | Up to three times more in one lab's studies, no gain from vitamin A in a later trial | May help |
Soak, sprout, ferment
Phytates in beans, lentils, whole grains, nuts and seeds hold plant iron back. They are not a reason to avoid these foods. Soaking, sprouting and fermenting wake the plant's own enzymes, which break phytates down.
- Soak dried beans and chickpeas overnight, pour off the water and cook them in fresh water.
- Sprout lentils, mung beans or buckwheat for 1 to 3 days before cooking.
- Ferment your bread: in one study long-fermented wholegrain sourdough let in as much iron as white rolls, with five times the fibre.
- Add vitamin C to every bean, grain or seed plate. It offsets phytates even when you skip the rest.
Cook iron porridge in water and add berries or kiwi.
Cook it in milk. The calcium undoes most of the gain.
Beans hold iron back with their skins' polyphenols too, so soaking alone helps less than it does for grains. Vitamin C and a little meat or fish matter most there.
Two plates
- Plant: lentils, raw red pepper, parsley and lemon, a slice of sourdough. Water to drink.
- Meat or fish: salmon or beef, roasted sweet potato, a squeeze of lemon. Coffee 2 hours later.
Questions
Do tinned beans need soaking?
No. They are ready to eat. Add lemon, parsley or raw pepper and they make a good iron meal.
Do carotenoids help iron?
Maybe. One lab found beta-carotene raised iron absorption from grain meals up to three times, but a later trial of vitamin A found no gain. Eat colour for its own sake, and count on vitamin C.
Does meat help even in small amounts?
From about 50 g, in one study. 25 g of pork made no clear difference, 50 g raised plant-iron absorption by 44% and 75 g by 57%.
Sources
- 1.Cook J.D., Monsen E.R. Vitamin C, the common cold, and iron absorption. American Journal of Clinical Nutrition, 1977
- 2.Baech S.B. et al. Nonheme-iron absorption from a phytate-rich meal is increased by the addition of small amounts of pork meat. American Journal of Clinical Nutrition, 2003
- 3.Hurrell R.F. et al. Degradation of phytic acid in cereal porridges improves iron absorption by human subjects. American Journal of Clinical Nutrition, 2003
- 4.Brune M. et al. Iron absorption from bread in humans: inhibiting effects of cereal fiber, phytate and inositol phosphates with different numbers of phosphate groups. Journal of Nutrition, 1992
- 5.Sandberg A.S. Bioavailability of minerals in legumes. British Journal of Nutrition, 2002
- 6.García-Casal M.N. et al. Vitamin A and beta-carotene can improve nonheme iron absorption from rice, wheat and corn by humans. Journal of Nutrition, 1998
- 7.Walczyk T. et al. No enhancing effect of vitamin A on iron absorption in humans. American Journal of Clinical Nutrition, 2003
- 8.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.