Prevention of iron deficiency anemia

Iron deficiency anemia or iron deficiency anemia is a public health problem in all countries of the world, especially in the poorest ones. It is estimated that between 20 and 30% of the world's population suffers from iron deficiency, making it the most common micronutrient deficiency in the world.

This type of anemia is more frequent in infants, children, adolescents, women of childbearing age, pregnant women and the elderly.

Diet plays an important role in iron deficiencies, so it is necessary to know the quantities and qualities of iron provided by food, as well as the existence of other dietary components and regulatory mechanisms that enhance or inhibit the absorption of this micronutrient, in order to prevent and treat anemia.

Anemia

Anemia is defined as a decreased concentration of hemoglobin in the blood, generally associated with a reduction in the number of red blood cells, which causes a deterioration of the oxygen transport capacity.

Among the multiple causes of anemia is the lack of certain vitamins and minerals that must be provided by the diet. Among the most important nutritional anemias are the following:

• Iron deficiency anemia: caused by iron deficiency, a mineral necessary for the formation of hemoglobin. It is the most common anemia.

• Megaloblastic anemia: caused by vitamin B12 deficiency, vitamin B9 deficiency and deficiency of both vitamins.

Iron deficiency anemia:

• Phase one (iron deficiency): occurs when iron stores are depleted, with all other parameters remaining normal. During this phase the levels of iron absorption from the diet or other supplements are increased.

• Phase two (erythropoietic deficiency): blood iron levels decrease, but there is no evidence of anemia.

• Phase three (iron deficiency anemia): hemoglobin synthesis decreases and anemia develops.

Iron deficiency anemia: Main causes of iron deficiency anemia:

• Deficiencies in iron intakes. They occur mainly due to deficient diets and/or poor eating habits.

• When diets are not adjusted to the increased iron requirements of the body. They occur mainly in stages of rapid tissue growth, as happens in women during pregnancy and during adolescence in both sexes.

• Excessive blood loss; they can be caused by alterations in the female menstrual cycle and by digestive microbleeds in both sexes.

• Difficulties in intestinal absorption; they can occur due to gastrectomies and in undiagnosed celiac patients or those who do not follow the appropriate treatment.

Physiological and dietary factors that influence iron absorption

Iron bioavailability: is defined as the efficiency with which iron obtained from the diet is biologically utilized. Despite the high iron content of some foods, its bioavailability can vary from less than 1% to 30%, depending on the interrelation of the following factors.

Physiological:

• Nutritional status of the person.

• Physiological states that require modification of iron mobilization or absorption.

Dietetic:

• Type of iron present in food.

• Amount of iron contained in food.

• Interactions between foods contained in the same meal.

Physiological factors that increase iron bioavailability:

• Acid secretions favor increased iron bioavailability.

Examples:

• Iron assimilation is higher when the stomach is empty, since there is a higher concentration of gastric juices, consisting mainly of hydrochloric acid and pepsin.

• When there is hypersecretion of hydrochloric acid.

• When there are states of oxygen deficiency in blood (hypoxic states) that compromise the function of cells, tissues and organs.

Examples:

• Anemia.

• Blood loss.

• High performance sports training.

Due to the increase of the total volume of circulating blood. Example: occur during pregnancy.

Due to iron and protein losses. Example: they can occur mainly due to infections.Blood loss. Example: they occur mainly in the female sex due to the occurrence of very heavy menstruation.

Physiological factors that reduce iron bioavailability:

• When sodium bicarbonate is taken.

• When iron reserves are high.

Types of iron in the human diet:

• Heme iron: found as part of two proteins contained in animal tissues, hemoglobin and myoglobin. It is found in blood, heart, kidneys, liver, red meat, poultry, fish, clams, mussels and oysters. It is much more easily absorbed than non-heme iron.

• Non-heme iron: it is contained in foods of plant origin, such as nuts, legumes, whole grains and some algae. It is also contained in foods of animal origin, such as meat, fish, eggs and milk.

Non-heme iron:

• Substances that contribute to the digestion of non-heme iron: certain substances contained in some foods, when consumed together with other foods rich in non-heme iron in the same meal, facilitate the assimilation of iron.

Examples:

• Ascorbic acid (vitamin c), present mainly in citrus fruits such as kiwi, lemon, orange, guava, and strawberries; also in vegetables such as red bell pepper, broccoli and tomato.

• Proteins contained in meats. Vitamin A, abundant in liver, as well as ß-carotenes, present in carrots, spinach and dried apricots, pumpkin, melon, peach and cherries, favor the absorption of non-heme iron.

Substances that hinder the digestion of non-heme iron: certain substances contained in some foods, when consumed together with other foods rich in non-heme iron in the same meal, hinder the assimilation of iron.

Examples:

• Phylates: these are compounds that inhibit the absorption of non-heme iron. They are present in foods of vegetable origin, especially in seeds, such as cereals and legumes, which are highly recommended foods in the diet.

• Polyphenols: they act as inhibitors in the absorption of non-heme iron. Polyphenols are found in vegetables, legumes, fresh fruits, nuts and beverages such as tea, coffee, cocoa, condiments, wine and beer.

• The minerals phosphorus, calcium and zinc.

Heme iron:

• The bioavailability of heme iron is very high, although it can be affected when high doses of calcium are consumed, if it is supplied in solution form (milk or yogurt). Calcium and iron deficiency anemia.

• Calcium intakes should be taken into account in cases of iron deficiency anemia because it interferes with the bioavailability of heme iron and non-heme iron. The effect of calcium depends on the amount; when doses are lower than 40 mg it does not interfere, however, between 40 and 300 mg, it does, and can reduce bioavailability up to 50%.

How to prevent iron deficiency anemia

The prevention of iron deficiency anemia is done through the following main strategies:

• Fortification of food with iron.

• Nutritional supplementation.

• Dietary intervention.

Food fortification with iron:

• Food fortification is a strategy that produces a favorable impact on the nutritional health of the lower income sectors of industrialized countries and the general population in developing countries.

• Fortification co