It is estimated that over 1.5 billion people worldwide suffer from iron deficiency anemia. The most common symptoms of this condition are dizziness, general weakness, concentration problems, and fatigue. Hair and nail weakness and skin paleness are also clear signs that may indicate iron deficiencies in the body. Iron deficiency is observed in nearly 30% of women of reproductive age worldwide, while anemia during pregnancy is observed at 38%.
Dietary iron occurs in two forms: heme and non-heme. The main sources of heme iron are animal products, such as red meat, poultry, fish, and seafood. Non-heme iron can be found in legumes, grains, and vegetables. Heme iron is better absorbed (15%-35%), and various dietary factors have little effect on its absorption. Non-heme iron has a much lower bioavailability (2%-20%), and its absorption depends largely on the presence or absence of other nutrients.
By combining certain foods, we can decrease or increase the absorption of iron. Phytates, which are present in large amounts in cereal flakes and legumes, are factors that limit the bioavailability of iron. A high amount of calcium in a meal, animal protein, and polyphenols, especially those from tea, also inhibit the absorption of iron.
The most important substance that increases iron absorption is ascorbic acid (vitamin C), which reduces the negative impact of the inhibitors mentioned above.
When following a diet aimed at increasing iron levels, it is worth considering additional supplementation with iron supplements. Products worth consulting with a doctor are lactoferrin and vitamin C. Lactoferrin is a protein present in breast milk, among others. Its mechanism of action involves binding iron ions and transporting them to the body's cells, protecting against excessive levels of free ions of this microelement. Vitamin C plays a significant role in iron metabolism. Studies show that consuming foods rich in vitamin C with a meal can increase iron absorption even twice. In the case of iron supplements, consuming them with vitamin C can increase their absorption by 4 to 6 times. However, it is important to remember that high iron absorption can also be harmful. The human body cannot remove excess iron. Therefore, iron of plant origin is more beneficial for the body. The degree of absorption of non-heme iron depends on many factors, while animal-derived iron in combination with supplementation can accumulate in the body to a harmful level for human health.
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