Vitamin A for growth and vision
When Vitamin A is, as in the case of Vitamin D, Vitamin E, and Vitamin K – a fat-soluble Vitamin. In colloquial language, is often set Retinol with Vitamin A is equal to, strictly speaking, it is the Vitamin A, however, not a single Vitamin, but a group of substances. These include retinoic acid and retinyl palmitate in addition to Retinol (Vitamin A1), for example, Retinal. Vitamin A can be ingested either directly through the consumption of foods of animal origin, or from the body from Provitamin A (Beta-carotene) contained in plant foods, are manufactured.
Effect of Vitamin A
Vitamin A is required in our body for the maintenance of the various processes. Particularly significant is it for vision. Here, the Vitamin A has especially an impact on the night – a deficiency can lead to night blindness. This is due to the fact that Vitamin A is the precursor for various Sehfarbstoffe and therefore for the differentiation of the colors and the Light and dark distinction is of crucial importance.
In addition, Vitamin A also influences the structure of the skin and mucous membranes by promoting cell growth. In addition, it prevents the skin cells, damage the DNA, respectively, supports the repair of this damage. In addition, Vitamin A is involved is also crucial in the formation of new red blood cells.
Since Vitamin A promotes the growth of skin and mucous membranes, it also has a positive effect on our immune system – the skin and the mucous membranes are healthy, bacteria or viruses to penetrate heavy in our body. In addition, Vitamin A also increases the number of leukocytes and thus strengthens our immune system. Therefore, the risk of developing cancer increases even a mild Vitamin A deficiency, the Two-to three – fold.
Vitamin A is important for our bones
Vitamin A is also involved in various metabolic processes in our body. It takes effect on the protein metabolism, but also on lipid metabolism. Due to its participation in protein metabolism, a protein-rich diet can have a Vitamin A deficiency.
A sufficient supply with Vitamin A is especially for children is of great importance. Because Vitamin A influences the development and growth of our bones and is particularly important for the healing process of bone fractures a crucial role. But for adults, Vitamin A is important since it plays in the synthesis of Estrogen and testosterone an important role. It also has an influence on the Oogenesis and the spermatogenesis and the number and the shape of the sperm depend on the supply with Vitamin A.
Vitamin A Acid
Vitamin A acid – Tretinoin or all-trans-retinoic acid is a degradation product of Vitamin A. The acid is, for example, in creams or alcoholic solutions used for the treatment of acne or other skin diseases, used. The Vitamin A acid cornification disorders are removed, the sebum production is inhibited, and it comes to a renewal of the skin.
However, acne treatment with Vitamin A acid usually has significant side effects, it can cause redness, Burning, itching, as well as a Blossoming of the acne. Therefore, the therapy with Vitamin A acid plays in comparison to other treatment options nowadays, it is only a subordinate role.
In addition, Vitamin A acid is also used in various cosmetics to prevent premature aging of the skin. To premature aging of the skin, it is light, especially by UV, since it inhibited the formation of Collagen and the degradation of collagen fibers promotes. Vitamin A acid can protect the skin against these two harmful processes and is therefore used in some Anti-Aging creams. Because of the use of the acid, however, skin irritation can occur, is used in Germany in creams, only the more harmless Retinol.
Vitamin A in foods
In foods of animal origin Vitamin A is in one of its forms – mostly as retinyl palmitate in foods of plant origin, it comes in the Form of Provitamin A (ß-carotene). Especially large amounts of Vitamin A are found in the following foods:
- Egg yolks
- Liver products (particularly beef)
Provitamin A is contained in carrot juice and in raw and cooked carrots. For more plant-based foods that have a high Provitamin A content are apricots, Cantaloupe, Kale, spinach, and pumpkin. In comparison to Vitamin A Provitamin A offers the advantage that it is converted in the body only when needed, into Vitamin A.
Daily requirement of Vitamin A
The daily requirement of Vitamin A can be met on both the supply of Vitamin A as well as Provitamin A (Beta-carotene). It is dependent on age, life circumstances and gender in men, the daily requirement is slightly higher than in women. The daily dose of Vitamin A for an adult at around 1 milligrams. Only Provitamin A is supplied, should be the daily dose to 2 milligrams. It provides the body with both Vitamin A and Provitamin A, is recommended a daily dose of 0.5 milligrams of Vitamin A and 1 milligram of Pro-vitamin A.
Since the Vitamin is able to tolerate only poorly with oxygen and light, one should store food containing Vitamin A is always dark and in the refrigerator. When cooking, the loss of Vitamin A is, depending on the cooking duration of between 10 and 30 percent.
Vitamin A in pregnancy
During pregnancy the need for Vitamin A in women is a little higher than usual. At this time it is particularly important that the mother and the child are sufficiently supplied with Vitamin A, since it has an important influence on the development of the child.
However, care should be taken during pregnancy, dose of Vitamin A is too high, as there may be a Overdose to deformities in the child. It stunted growth, liver damage, damage to the eyes as well as skin changes can occur.
Mainly because liver contains large amounts of Vitamin A, is discouraged their consumption during pregnancy. Similarly, you should not rely on dietary supplements that contain Vitamin A such as Vitamin A tablets. The intake of Provitamin A during pregnancy as safe.
Hypovitaminosis: a lack of Vitamin A
Vitamin A in the body is not enough, it can lead to hypovitaminosis. The at-risk group for Vitamin A deficiency older people, young women, infection-prone children as well as premature babies. Typical symptoms of hypovitaminosis are:
- Increased susceptibility to infections
- Reduced Visual Acuity
- Dryness of the hair, nails, eyes, and hair as well as hair loss
- Impaired sense of smell and touch, as well as decreased appetite
By a Vitamin A deficiency can be increased diseases the risk for atherosclerosis, as well as a possible consequence, for cancers in organs that have a mucous membrane, for fertility and for the formation of kidney stones.
Just as numerous as the possible consequences of the causes of Vitamin A deficiency. These include Stress, inflammation, and operations, serious illnesses such as cancer, Arthritis or Aids, environmental toxins, Smoking, alcohol, as well as strong sun light. In addition, laxatives and cholesterol-lowering drugs impair the absorption of Vitamin A, while by the intake of certain sleeping pills be used up, the Vitamin A reserves in the liver. In addition, people who suffer from Diabetes or an overactive thyroid have problems, herbal Cartinoide in Vitamin A convert.
A Vitamin A deficiency, increased emphasis should be given foods that are rich in the Vitamin is consumed. In addition, if a disease is the cause of Vitamin A deficiency, the disease to be treated.
Hypervitaminosis: Overdose of Vitamin A
Just as with other fat-soluble vitamins, an Overdose of Vitamin A is harmful for the health. An Overdose, however, can only arise by the intake of too much Vitamin A, that is, by too many animal foods, but not by too much Provitamin A. Because if we take too many carotenoids to us, driving our body, the conversion into Vitamin A down. By the ingestion of large amounts of carotenoids can lead to a yellowing of the skin.
In the case of an Overdose, there is a difference between acute hypervitaminosis, which is caused by the absorption of A lot of Vitamin A within a short period of time, and a chronic hypervitaminosis, which comes by taking too much Vitamin A over a long period of time. To an acute Overdose of Vitamin A, for example, large quantities of fish – or seal liver. There are symptoms such as headaches, dizziness and vomiting can occur. Is fed over several weeks Vitamin A in large amounts, it can also cause a complete loss of body hair.
Over a longer period of higher doses taken in Vitamin A, this can have more serious consequences: It can lead to increased intracranial pressure, calcium excess, with consequences such as high blood pressure and kidney failure, growths of the periosteum, as well as an enlargement of the liver and the spleen. This is due to years of too high a dose of Vitamin A poisoning, which can also lead to death.