Vitamin A


Vitamin A (retinol) Vitamin A was discovered in 1940. It was called a «growth factor»: when this vitamin was completely excluded from the diet of experimental mice, the growth of animals stopped and they died. This fat-soluble vitamin can be stored in the liver and used as needed. It can enter the human body in its «real» form or be formed from another substance — beta-carotene, which is called the prototype of vitamin A, or a precursor of vitamin A. Why is it needed? As already mentioned, vitamin A is important for the normal growth of the organs of children and expectant mothers. Its role is great in the processes of renewal and restoration of skin cells, the functioning of mucous membranes; it contributes to the proper functioning of the organs of vision, hearing, smell and touch, and the activation of immunity. This vitamin is involved in the metabolism of fats and in the synthesis of proteins, as well as in the formation of visual pigments — substances contained in retinal rods (due to visual pigments, black-and-white and color vision is formed). In addition, vitamin A is involved in the construction of bones and teeth, slows down the aging process. During pregnancy, its role is important in stimulating the reproduction of erythrocytes — red blood cells that transport oxygen to tissues. It increases resistance to diseases of the mucous membranes of the respiratory tract and intestines. In the postpartum period, vitamin A provides recovery processes in the mother’s body. Sources The main sources of vitamin A are fish oil, liver, kidneys, eggs and dairy products, especially milk and butter. In the form of beta-carotene, vitamin A is found in yellow-red and green vegetables: carrots, sweet and capsicum peppers, tomatoes, various types of cabbage, pumpkin, legumes (soybeans, peas). A lot of beta-carotene in some fruits: peaches, apricots, apples, grapes, watermelon, melon, rose hips, sea buckthorn, cherries. Vitamin A contains herbs: alfalfa, borage leaves, burdock root, fennel, hops, horsetail, nettle, oats, mint, clover, sage, sorrel. Daily value The daily requirement for vitamin A during pregnancy is 2667-3300 IU (international units). 1 microgram of vitamin A (retinol) = 6 micrograms of beta-carotene = 3.3 IU Vitamin A, found in fruits, vegetables and greens, is better absorbed if you eat a little fat at the same time (salad vegetable oil or sour cream, cream, milk, cheeses). Vitamin A deficiency The manifestation of this condition is a violation of twilight vision (the so-called night blindness, in which a person sees almost nothing in low light), watery eyes in the cold, a feeling of «sand» in the eyes, myopia and eye fatigue, redness of the eyelids. With a lack of vitamin A, the keratinization of the upper layers of the skin increases, the secretion of the sebaceous and sweat glands decreases. This leads to the fact that the skin becomes dry, wrinkles appear early, the condition of the hair worsens (they lose their shine and begin to fall out), dandruff appears, the nails become thinner and brittle, and resistance to infectious diseases decreases. Excess of vitamin A Excess of vitamin A can be manifested by loss of appetite, weight loss, nausea, drowsiness, gait disturbance. There may be changes in the kidneys, the central nervous system, itching appears. Be careful! During pregnancy, an excess of vitamin A can cause malformations of the central nervous system, heart, kidneys, genitals and limbs of the fetus. It should also be borne in mind that an excess of vitamin A impairs the function of vitamin D and increases the symptoms of its deficiency. That is why it is so important for pregnant women to take a special multivitamin for pregnant women, which contains a daily dose of vitamin A.


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