Inhibitors of iron absorption are compounds that can reduce the amount of iron that the body can absorb from food. Some of the most common inhibitors of iron absorption include:
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Phytates: These are compounds found in plant-based diets, such as whole grains, cereals, soy, corn, nuts, and legumes. Phytates can block the absorption of non-heme iron, which is the type of iron found in plant-based foods.
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Polyphenols: These are compounds found in black and herbal tea, coffee, wine, legumes, cereals, fruit, and vegetables. Polyphenols have been shown to inhibit iron absorption.
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Calcium: Calcium inhibits both heme and non-heme iron at the point of initial uptake into enterocytes. Calcium-rich foods, such as milk and dairy products, can hinder iron absorption.
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Oxalic acid: Oxalic acid is found in some foods, such as spinach, rhubarb, and beet greens. It can bind to iron and reduce its absorption.
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Egg yolks: Egg yolks contain a compound that can interfere with iron absorption.
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Soy proteins: Soy proteins can reduce absorption from plant sources.
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Tannins: Tannins are found in tea, coffee, and wine. They can reduce iron absorption by binding to the iron and carrying it out of the body.
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Phytates and fibers: Phytates and fibers found in whole grains, such as bran, can reduce the absorption of iron and other minerals.
To increase iron absorption, it is recommended to consume vitamin C, which can enhance iron absorption by capturing non-heme iron and storing it in a form that the body can absorb more easily. Animal protein (haem) with plant (non-haem) sources of iron, such as meat with beans, can also help improve iron absorption. Cooking plant sources of iron, such as vegetables, can increase the amount of available non-haem iron in them. On the other hand, it is best to avoid consuming inhibitors of iron absorption with iron-rich foods.
