Iron
An important mineral, iron helps maintain blood health. It is a primary component of hemoglobin, a protein in red blood cells that carries oxygen to all parts of the body from the lungs, and part of myoglobin, a protein that transports and stores oxygen in our muscles. Iron is important for childhood brain development and growth, as well as the production and functioning of myriad hormones and cells.
Iron from food comes in two forms: heme and non-heme. Heme iron is found predominantly in blood and muscle, whereas non-heme iron is primarily found in plants, such as whole grains, nuts and seeds, legumes, and leafy greens. We used to think of heme iron as coming exclusively from animal products and non-heme iron as found only in plants, but that isn’t the case. The plant-based Impossible Burger contains heme iron derived from soybean plants, for example, and non-heme iron can be found in meat if the animal had consumed plant foods with non-heme iron.
Compared with people who eat meat, vegetarians tend to consume more iron (and more of most nutrients), but since the iron in plants is not absorbed as efficiently as the heme iron in meat, about 1 in 30 U.S. menstruating women may lose more iron than they take in, which can lead to anemia. Women who eat plant-based diets don’t appear to have higher iron deficiency anemia rates than women eating a lot of meat, but all women of childbearing age should ensure adequate iron intake.
Those diagnosed with iron deficiency should talk with their doctors about first trying to treat it with diet, as iron supplements have been shown to increase oxidative stress. The healthiest iron sources are whole grains, legumes, nuts, seeds, dried fruits, and green, leafy vegetables, which can be paired at the same meal with vitamin C-rich foods such as citrus, bell peppers, broccoli, and tropical fruits to boost iron absorption.
The information on this page has been compiled from Dr. Greger’s research. Sources for each video listed can be found by going to the video’s page and clicking on the Sources Cited tab. References may also be found at the back of his books.
Image Credit: robynmac / Thinkstock. This image has been modified.
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Risk Associated with Iron Supplements
Iron is a double-edged sword. If we don’t absorb enough, we risk anemia; but if absorb too much, we may increase our risk of cancer, heart disease, and a number of inflammatory conditions. Because the human body has no mechanism to rid itself of excess iron, one should choose plant-based (non-heme) sources, over which our body has some control.
