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Iron on a plant based diet: what the doctors say
Iron on a plant based diet: what McDougall, Campbell, Barnard and Rogers say about anemia, iron overload, pills and absorption, with sources.
Updated . For education only, not medical advice.
Our view
Iron is an element that plants draw up from the soil; Barnard points out that the iron stored in a cow’s liver came from the grass the animal ate, and McDougall describes a diet of starches and vegetables as rich in it12. Neither accepts that skipping meat sets people up for anemia: Barnard says blood studies find vegans no more often anemic than meat eaters, and in 2026 he added that the typical vegan actually takes in more iron34.
Fewer doctors on this site speak about iron than about B12, and those who do worry less about too little iron than about too much, or about a hidden cause behind a low result567. Plant iron is the non heme kind, which the gut lets in more freely when stores are low and holds back when they are full, while the heme iron in meat gets in either way89.
We give most weight to the low-fat clinicians without a product to sell, and they share a practical rule: when iron or blood counts come back low, look for the cause, most often blood loss, before reaching for a pill10113. Peter Rogers goes furthest, arguing that in Western countries overload is common and anemia fairly rare7, and in 2024 McDougall agreed that high iron can harm the body while doubting part of the evidence for giving blood to lower it12.
Where they agree
Plant foods supply enough iron, in their view: McDougall writes that study after study finds vegetarians’ blood iron on a par with that of meat eaters, the Ornish program’s site says surveys show vegetarians are no more prone to a shortfall, and Campbell said his China study found almost no anemia among people eating mostly plants131415. Barnard and the Ornish site name beans, lentils, leafy greens and soy foods among the sources161718.
They agree that vitamin C from fruits and vegetables helps the body take up plant iron; McDougall, Barnard and the Ornish site all make that point191720. McDougall and Barnard also agree that dairy works against iron: McDougall explains that the calcium and phosphorus in milk bind iron so the gut cannot absorb it, and that cow’s milk can make a child’s intestine bleed, while Barnard said in 2014 that drinking milk alongside food roughly halves the iron taken up2122.
Most of them also see excess iron as a hazard, because iron drives oxidation: Ornish listed it among the oxidants to limit in 1999, McDougall and Barnard tie too much of it to heart disease, and Barnard adds a possible link to dementia23126. Barnard and Rogers both say the body can regulate how much plant iron it absorbs but cannot do the same for the heme iron of meat824.
Where they differ
The doctors part ways on how much a plant based eater should worry about running short, whether iron pills have a place, which foods and habits change absorption, and how to check and lower iron levels2572627.
Shortage or overload
Rogers puts the weight on overload: in a 2022 lecture he said a Western diet supplies far more iron than people need, and in 2026 that most men over 25, and most women once their periods stop, carry too much287. The Ornish program’s site, archived in 2025, leans the other way, listing iron among the minerals that can run low on a vegan diet depending on food choices and suggesting that vegetarians who rely on plants aim for 1.8 times the usual intake2518. Rip Esselstyn’s PLANTSTRONG site, writing for women in 2026, notes that women run short more often than men, above all in pregnancy or with heavy periods29. McDougall sees heavy periods themselves as partly a product of the Western diet, whose fat raises estrogen and thickens the lining of the uterus3031.
Iron pills
McDougall said in 2024 that iron pills are usually unnecessary, warning that they constipate, turn the stool black and over the long run may raise heart risk, though a short course is tolerable32. Barnard said in 2020 that people in doubt should not go out and buy iron pills but ask their doctor for a blood test, and a 2026 episode of his group’s podcast covers both when a supplement may be needed and the risks of iron taken without medical supervision2633. Ornish takes a multivitamin with no iron, as his program’s guidelines advised in 2011 for people not of childbearing age, and Goldhamer said in 2024 he was glad to see a multivitamin leave iron out343536. Chef AJ, found to be iron deficient in 2026, refused the pills her doctors offered because they had upset her digestion in pregnancy, and asked for an infusion instead37.
What helps or hinders absorption
On phytates they read the same chemistry in opposite ways: the Ornish site treats the phytates in beans and whole grains as a brake on absorption that soaking, sprouting, fermenting and cooking can ease, while Rogers welcomes plant iron bound to phytate because, in his view, the bound form cannot set off damaging reactions3839. McDougall’s anemia page lists coffee and tea as drinks that reduce absorption, and calls the worry that fiber blocks minerals a theory with almost no real cases behind it4041. On cast iron pans, Barnard said in 2014 that they add iron to food, a plus for someone who is low and a minus for someone who is high, and offered stainless steel as the alternative42. Rogers goes further on fortified foods: he says he would never eat anything with added iron43.
Testing and giving blood
McDougall’s first step with low iron or a low blood count is a search for blood loss, from the bowel or, in women, the uterus, and in 2024 he called it malpractice to skip that search1110. Barnard says much the same, noting that anemia later in life always raises the question of colorectal cancer3. Rogers aims for a ferritin of roughly 30 to 80, found his own at 240 and gave blood to bring it down, though he felt faint afterwards and now advises donating a small amount, well hydrated, the first time27. McDougall, asked about this view in 2024, accepted that high iron may be toxic but noted that the lower heart risk of blood donors could partly reflect that careful people both donate and look after their health12.
Older views
Barnard traces how the advice changed: in the 1950s more iron was thought better, with liver, red meat and iron tonics promoted for tired blood, until excess iron was linked to heart disease and later, possibly, to dementia446. Ornish already counted iron among the oxidants to avoid in a 1999 interview23.
What each expert says
JMJohn McDougall
McDougall said in 2022 that a lack of iron almost never comes from what people eat but from blood loss, often unseen, or from poor absorption, with dairy the usual culprit5. He told a 2017 webinar that his starch-based diet is rich in both iron and zinc2. In 2024 he advised a blood donor with slow-recovering iron to rule out blood loss, eat fruits and vegetables for their vitamin C, drop all dairy and skip pills unless truly needed101932.
In a 2023 Q&A Campbell said his China study measured iron status five ways in some 6,500 people eating mostly plant foods and found hardly any anemia15. For an anemic person he suggested a medical workup that checks for causes such as parasites, and said that on the diet side there is no need for the heme iron of meat45.
Barnard holds that plants give enough iron in a form the body can regulate, while heme iron from meat enters whether needed or not and can lead to overload84. He connects surplus iron with heart disease and perhaps dementia, citing in 2014 a Chicago study in which brain function suffered at both low and high hemoglobin466. For anyone unsure of their iron, he prefers a blood test from their own doctor to pills bought on a hunch26.
In a 1999 radio interview Ornish named iron among the oxidants that eating low-fat plant foods keeps in check23. His program’s guidelines, archived in 2011, recommended an iron-free multivitamin to anyone past childbearing age, and in 2019 he said his own has none3534. The program’s site, archived in 2025, says surveys find vegetarians short of iron no more often than other people, and that the vitamin C in plant foods strongly boosts absorption1420.
Answering a question about a multivitamin in 2024, Goldhamer said he was glad it left out iron, which he counted with vitamin A among ingredients that can seriously harm health36. Making a family dinner on camera in 2022, he topped the salad with a few raw pumpkin seeds and mentioned that they are rich in iron47.
Rogers sees iron overload, not shortage, as the common problem, and describes iron that builds up over the years as a slow poison287. He welcomes plant iron bound to phytate, avoids every food with added iron and suggests keeping ferritin roughly between 30 and 80, which led him to give blood himself394327.
Writing in 1999, Novick reported a study of wild monkeys whose diet of fruit and leaves supplied far more iron than most human diets48. In a later piece defending iceberg lettuce, he counted iron among the nutrients even a small serving supplies, about 9 percent of a day’s need in 25 calories49.
Rip Esselstyn’s PLANTSTRONG site recommends beans to women in part for their iron, which the body uses to make hemoglobin29. The 2026 article points out that women are short of iron more often than men, especially during pregnancy or with heavy periods29.
In a 2026 broadcast Chef AJ said she had become anemic and iron deficient, with the cause not yet known50. Her doctor told her to pair greens with vitamin C, and she named pumpkin seeds and quinoa as plant sources, but she turned down iron pills and asked for an infusion, since pills had upset her digestion in the past37.
We rely on beans, lentils, leafy greens and seeds for iron and eat them alongside fruits or vegetables rich in vitamin C, as McDougall, Barnard and the Ornish program suggest191720. We keep dairy out and do not take iron pills or a multivitamin with iron on our own, in line with McDougall, Barnard and Ornish322634. If a blood test shows low iron or anemia, the doctors on this page agree that finding the cause comes first, and that is work to do with your own doctor. This page is education, not medical advice.
Each small number links to its reference below: the video at the exact second, or the page where it was said.