Vitamin A: what it is, functions, daily needs and food
The Vitamin A (also called axeroftol or retinol), is well known for a long time for its essential role on the organ of sight, especially because it is necessary for the formation of the visual pigments of the retina, that allow the adaptation of the vision when the light decreases.
He also has numerous other important and essential roles in what concerns growth factor and renewal of mucous membranes and skin cells, intervening in the body's resistance to infections, and in the formation of certain hormones.
Unlike other vitamins like vitamin B1, our body has quite important reserves of Vitamin A, especially at the level of the liver, which normally has sufficient quantities to cover the needs for several months.
The importance of these reserves explains that, for example, poisonings can occur due to Vitamin A if excessive contributions are made.
What is vitamin A?
The Vitamin Ais a vitamin popularly known by the name of retinol, although it is also less known by the name of antixeroftálmica. It is characterized by being a fat-soluble vitamin, which means that it is a nutrient that does not solubilize in water, but does in fat.
That is, vitamin A is an essential nutrient capable of being stored in the fatty tissues of our body, especially in the liver and adipose tissue, so that an excess in its consumption can cause problems of toxicity, since its elimination by part of our body tends to be more difficult.
In fact, the toxicity of vitamin A can cause alterations in the skin, bones, visual and teratogenic disorders (pregnancy can cause malformations of the fetus).
As we will see below, there are different types of vitamin A, there are other molecules known as carotenoids, which function as provitamin A, when it is transformed into liver and intestine (the most abundant is β-carotene or beta-carotene). ).
Do you know that there are two types of vitamin A?
There are two types of vitamin A depending on their origin:
- Preformed Vitamin A: found in foods of animal origin and derivatives, such as beef, poultry, fish and dairy products.
- Provitamin A: we find it in vegetables, fruits and other foods and products of vegetable origin.
Functions of vitamin A. What is it for?
- It helps in the formation and maintenance of teeth, white tissues, bones, mucous membranes and skin.
- It favors good vision, especially in dim light. In addition, it produces the pigments in the retina of the eye.
- Intervenes and participates in reproduction processes.
- Participate in the natural immunity of our body.
- It favors, in pregnancy, that the embryo develops normally.
- Advisable during breastfeeding.
Recommended daily amounts of vitamin A
|Age||Men (ug / day)||Women (ug / day)|
|+ 11 years||600||600|
|+ 15 years||700||700|
The best way to obtain the recommended daily requirements of vitamin A is to consume a complete and varied diet, rich in fruits, vegetables, legumes, whole grains, meat and fish.
It is important to keep in mind that the amount of each vitamin, as with vitamin A, that each person needs depends on age and sex, as well as other factors, such as pregnancy, lactation or health status of the individual.
Consequences of vitamin A deficiency
Although the deficit Vitamin A It is difficult to produce it since we find it in a great diversity of foods, it is possible that it appears.
When vitamin A deficiency is mild or marginal, the person may suffer from a weakening of the immune system, which will lead to a greater susceptibility to infections, especially in the epithelia of the respiratory tract, or to skin problems.
When the deficiency is more severe, the person may notice a loss of vision when various physical changes occur in the eye, especially in situations of both dim light and night. If the deficiency is maintained, it could lead the person to blindness eventually.
Therefore, the best way to provide vitamin A to our body is by adopting a balanced and complete diet, but without overdoing it since an excess can produce hypervitaminosis, and water or chronic intoxication.
Food sources of vitamin A
Foods rich in vitamin A or retinol
Vitamin A content
Halibut liver oil
Liver of lamb
Cod liver oil
In addition to the foods listed above, we can also find vitamin A in fruits such as apricot, mango, melon and peach, or in vegetables such as pumpkin. Also in legumes such as peas.
Foods rich in β-carotene
They emphasize above all foods like green vegetables. They also include carrots, spinach, cabbages, sweet potatoes, lettuce and broccoli.
Content of β-carotene