Iron: Interactions

Interactions of iron with other micronutrients (vital substances):

Vitamin C

To promote absorption of iron by reduction to Fe2+, 25 mg to 75 mg or more of vitamin C must be present in a meal. It is also possible that vitamin C increases the stability of intracellular ferritin. As a result, phagocytosis of ferritin into lysosomes, and thus conversion to difficult-to-available hemosiderin, is prevented.When iron is taken orally (iron supplementation), absorption is improved by simultaneous administration of vitamin C-rich fruit juices.

Vitamin A

Vitamin A deficiency can worsen anemia caused by iron deficiency. Scientific studies found that vitamin A supplementation has beneficial effects on iron deficiency anemia and improves iron status in children and pregnant women. Combined intake of vitamin A and iron showed better therapeutic success of anemia than either iron or vitamin A alone.

Calcium

When calcium is taken with iron within a meal, the calcium present may decrease the absorption of the iron. However, supplementing the diet with 1,000-1,500 mg calcium/day showed little effect on ferritin (iron storage) levels.

Copper

Balanced copper status is important for healthy iron metabolism and erythrocyte (red blood cell) formation. Therefore, anemia may be a symptom of copper deficiency. Studies in animals prove the important role of copper in iron absorption, iron was further found to be increased in the liver of copper deficient animals. This fact proves that copper is important for iron transport to the bone marrow and thus for erythropoiesis (the process of erythrocyte formation and development).

Manganese

Iron and manganese compete for the same absorption and transport mechanisms. This results, for example, in decreased manganese absorption from a meal if the meal also contains iron. Iron supplementation – 60 mg/day for 4 months – resulted in decreased serum manganese levels and decreased manganese superoxide dismutase activity in leukocytes (white blood cells). This condition indicates a decreased manganese nutritional status. Iron status may affect the bioavailability of manganese: Intestinal absorption of manganese is increased when iron deficiency is present – in contrast, full iron stores – detectable by serum ferritin levels – result in decreased manganese absorption.

Zinc

Absorption of zinc may be impeded if high doses of iron are taken with zinc as a supplement on an empty stomach. When iron is taken as a supplement along with food, the iron does not appear to inhibit zinc absorption. Foods fortified with iron have no effect on zinc absorption.