Vitamins A groups collect substances with similar biological effects. They include retinal(aldehyde - vitamin A), retinol(alcohol - vitamin A), retinoic acid(acid - vitamin A). In its pure form, it was isolated by Mendel and Osborne from butter. Scientists have discovered this vitamin in fish oil, full-fat milk, cream, butter and full-fat cottage cheese, egg yolks, cheese, liver, heart and brain. The amount of vitamin in products of animal origin directly depends on the type and composition of food that the animal itself consumes. Therefore, fish oil is 100 times richer in retinol than, for example, butter, because the plant plankton that fish eat is precisely saturated with vitamin A.

Effect of vitamin A

Vitamin A guarantees the integrity of the cells responsible for the formation of mucous membranes and skin, and it also accelerates the healing process of the skin in case of damage. Composition of many cosmetics contains its analogs that have a beneficial effect on the skin.

Both vitamin A and -carotene, being strong antioxidants, are means for treatment and prevention cancer diseases .

Daily value of vitamin A

Vitamin A (retinol) has the ability to accumulate in the liver. With very long use of retinol in increased doses, it begins to become toxic to the body. The daily dosage of vitamin A is different for absolutely all age groups and gender groups of people. Men need to get 650-950 mcg of vitamin A per day, and women 600-800 mcg, but for pregnant women daily requirement in vitamin A increases by 100 mcg, and for nursing mothers - by 410 mcg of this vitamin. The children's required daily dose of retinol is in the range of 400-1000 mcg. In case of acute deficiency, the dosage is increased to a maximum of 3000 mcg. Vitamin A is best absorbed with fatty foods. It is important to consider that when processing and cooking food, 10-40% of retinol is lost. We must remember this when preparing food rich in vitamin A.

Vitamin A deficiency

Lack of vitamin A leads to “night blindness” - this is the very first and most important sign indicating its deficiency. How can it be detected? You just need to leave a well-lit room and go into a dark one. If at the same time your eyes adjust to darkness for more than 8-9 seconds, you may not have enough vitamin A; if it takes more than 15-25 seconds, then you need to see a doctor! If it only takes a few seconds for you to do this, then everything is fine and your body has the normal level of vitamin A.

In China and Ancient Egypt“Night blindness” was cured by dishes prepared from half-raw liver. Liver juice is the most generous source of vitamin A. This complex compound comes in a number of forms. But two of them are significant for us: vitamin A, which is obtained from animal sources, carotene, and retinol, obtained from plant sources.

A lack of vitamin A in the human body is also indicated by a burning sensation under the eyelids, pain in the eyes from bright light, and “goose bumps” on the hips and elbows. In children, this is a delay in development and growth.

One of the initial signs of insufficient vitamin A in the human body is tightness and dryness of the skin. Accordingly, any diseases of the skin structures indicate that our diet must certainly include foods enriched with vitamin A.

What are diseases of the skin structures? This is atrophy of the sweat glands, dryness of the mucous membranes: the oral cavity, paranasal sinuses, nostrils, trachea, bronchi, i.e. diseases associated with disorders of the respiratory tract, - all this is directly related to the amount of vitamin A in the body. One has only to increase the dosage of this vitamin and all problems will be eliminated. Even psoriasis, in some cases, can be cured by increasing the dosage of vitamin A.

Indications for the use of vitamin A:

A popular component of anti-aging creams and one of the usual reasons to purchase fish oil is vitamin A.

It received its letter designation for being the first vitamin discovered.

Back in 1913, it was described by two independent groups of scientists.
This vitamin also has other names: trans-9,13-Dimethyl-7-(1,1,5-
trimethylcyclohexen-5-yl-6)-nonatetraen-7,9,11,13-ol and more familiar to our ears - retinol.

As it turns out?

This fat-soluble vitamin is not found in nature in its pure form. And in food a person can get two of it different ways. The simplest is from animal products, where retinol is contained in a form ready for absorption.

More complex - from plants containing red vegetable dyes carotenoids, which are converted in the body into vitamin A. They got their name thanks to the English name for carrots - carrot - from which they were first isolated.

The most famous carotenoid that supplies the body greatest number vitamin A – beta carotene- turns into it as a result of splitting in the liver. Carotenoids can be found not only in plants - they are found in algae and even mushrooms.

Why is it needed?

The best known role of vitamin A is to provide good vision. It helps synthesize the retinal visual pigment rhodopsin, which helps capture even the weakest light and is responsible for night vision.

Retinol is also involved in the secretion of tear fluid, which protects the cornea from drying out. And the carotenoids lutein and zeaxanthin reduce the risk of developing cataracts and slow down the processes of degeneration in the visual apparatus.

Men may notice a deficiency of this vitamin in the form of weakening erection and premature ejaculation. Frequent respiratory diseases and a serious decrease in work ability are also signs of vitamin A deficiency.

What prevents it from being absorbed?

Since vitamin A is fat-soluble, an insufficient amount of fat in the diet, for example, with a strict unbalanced diet, seriously impairs its absorption by the body.

For those who are engaged in weight loss using biological active additives, you should carefully read their composition. If they contain mineral oils, used as laxatives - Vaseline or castor - they can dissolve vitamin A and remove it from the body.

Vitamin A is poorly absorbed in those who abuse alcohol and smoke - due to disruption of the liver, which promotes the absorption and storage of retinol.

The absorption of vitamin A and the deficiency of its “partner” - vitamin E - and zinc impairs.

What to eat?

Most retinol is found in fish oil and beef liver. There is enough of it in dairy products - milk, cream, butter and cheeses, as well as chicken eggs.

Almost all bright yellow and red vegetables and fruits, as well as dark green leafy crops such as spinach, broccoli or green onions, are rich in carotenoids. There are carotenoids in legumes.

Together with fats, beta-carotene is absorbed 30 percent better. But only if it enters the body on an empty stomach, so this is not a reason to consume excess fat. For normal absorption of beta-carotene, the fats that a person receives during the day from food are sufficient.

The most important

Vitamin A is necessary for good vision, immunity and beautiful skin and hair. You can get it in two ways - from animal products and plant foods, which contain it in the form of provitamin A.