What is vitamin A
Vitamins are regulators of biological processes, without which the biochemistry of the body and the functioning of organs are disrupted. Most of them come from food, and some are synthesized by the body or intestinal flora. Vitamins are divided into water-soluble and fat-soluble. The former do not stay in the body for a long time and are excreted with metabolic products, while the latter accumulate in the liver. We wrote about vitamin D - the only one that affects the body's immune defense. But C turned out to be not as useful as dietary supplement manufacturers write about it.
Vitamin A is fat soluble. A person receives it from food in the form of precursors - retinoids and carotenoids. They are contained in the fatty depot of the liver, and when needed they are converted into retinol and sent to the tissues. Vitamin A regulates embryogenesis, the functioning of reproductive organs, skin glands, inflammation, the creation of new cells and their death. A retinol derivative is one of the components of rhodopsin. This is an eye pigment responsible for color perception.
External retinoids are used in dermatology: they treat acne and are prescribed to prevent age-related skin changes. It has been proven that isotretionine prevents the enzymatic degradation of collagen, the main structural component of the skin. Vitamin A derivatives are added to sunscreens for antioxidant protection.
“Vitamin A is used externally for many dermatoses, especially those associated with impaired keratinization, sebum secretion and healing,” says Nina Sergeeva, a dermatologist at the Fantasy children’s clinic. “It accelerates the restoration of skin integrity, reduces sebum production and regulates keratinization.”
Systemic retinoids are treatments for severe acne, psoriasis, rosacea, precancerous lesions, and nonmelanoma skin cancer. They normalize the formation of cells in the upper layer of the epidermis, reduce sebum secretion and inflammation, providing long-term remission. They are prescribed in cases where external therapy is ineffective or gives temporary results.
As it turns out?
Sources of retinol
If natural vitamins from animal products are not enough in the diet, then the recommended daily dose can be obtained from almost any vitamin complex.
This fat-soluble vitamin is not found in nature in its pure form.
And in food a person can get it in two 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 into vitamin A in the body. They got their name thanks to the English name carrot - carrot - from which they were first isolated.
The most famous carotenoid that supplies the body with the largest amount of vitamin A, beta-carotene
, is converted into it as a result of breakdown in the liver. Carotenoids can be found not only in plants - they are found in algae and even mushrooms.
How to understand that vitamin A is low
Every year, 500 thousand children around the world die from a lack of vitamin A, and 250 thousand go blind due to corneal opacity. Residents of Asia and Africa are mainly affected - this is due to early weaning and lack of vitamin A in the diet. At risk are people who have impaired absorption of zinc and fats, as well as those who abuse alcohol.
Vitamin A deficiency is visible externally. A person’s eyes and mucous membranes “dry,” he has difficulty finding his way in the dark and often gets sick. The skin becomes “toad-like” - strewn with small tubercles due to follicular hyperkeratosis - an accumulation of horny scales at the mouths of the hair follicles. If you do not replenish the vitamin A balance in time, you can go blind: the cornea will “dry out” and become opaque.
“Since vitamin A and carotenoids play a large role in the growth of cells and tissues, insufficient intake of the substances can lead to weakening of the skin,” says GMS Clinic dermatologist Nadezhda Nabatnikova. “Dryness, irritation and acne occur, after which the skin heals worse or slowly, and scars appear.”
Why is it needed?
The most well-known role of vitamin A is ensuring 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.
Retinol is involved in the functioning of the immune system.
It improves the functioning of nonspecific protective factors
- the barrier functions of mucous membranes, for example, in the mouth or nose.
In addition, vitamin A increases the activity of leukocytes - white blood cells that destroy foreign particles that enter the body. Both retinol and carotenoids are powerful antioxidants
that can neutralize the most dangerous types of free radicals (aggressive fragments of molecules that destroy body cells).
This vitamin helps the skin's healing
and its natural renewal.
It is used to produce cosmetics and medicinal products, for example, for acne and acne. Vitamin A is added to anti-aging cosmetics, as retinol stimulates the production of collagen, which maintains skin elasticity. It is also included in tanning products - in case of sunburn of the skin, retinol accelerates its regeneration. Retinol takes part in the production of human sex hormones
and is very important during intrauterine nutrition of the embryo.
What to do
If you are concerned about the quality of your skin, order vitamins early. First you need to go to the doctor and find out what the reason is. Maybe the body does not have enough iron, or the person has hypothyroidism - only an examination will determine this. If the indicators are normal, the doctor will prescribe a test for vitamin levels in the blood. When there are few of them, the diet is first changed. Supplements are prescribed only to those who have digestive problems.
“Most vitamin A comes from foods rich in beta-carotene and provitamin A carotenoids. These are powerful antioxidants. They neutralize the effect of free radicals, which break down collagen and contribute to the appearance of wrinkles, explains Nadezhda Nabatnikova. “The substances also reduce skin sensitivity to ultraviolet rays, providing natural protection against redness and pigmentation caused by the sun.”
The norm for a person from the age of four is 5000 international units of vitamin A. He should receive it from food of animal and plant origin. The best source is cod liver. One teaspoon of its oil contains 150% of the daily requirement. A lot also contains beef liver, salmon fillet and tuna. The plant richest in vitamin A is sweet potato, one hundred grams of which covers the daily requirement. Kale, winter squash and turnips contain it in abundance, with carrots only coming in sixth. Important: heat-treated root vegetables are taken into account, not raw ones.
Some people, tired of acne, buy systemic retinoids and take dosages from the Internet. This is dangerous - if the dosage is exceeded, these drugs cause fetal malformations - auricular atresia, underdevelopment of the limbs, atrial septal defect and displacement of large vessels. Therefore, a dermatologist prescribes systemic retinoids after a pregnancy test and the patient’s commitment to use double contraception - hormonal pills plus a condom.
“When using systemic retinoids and other vitamin A preparations, a teratogenic effect on the fetus is possible. Therefore, even before taking dietary supplements, and even more so medications, it is worth consulting with your doctor,” says Nina Alexandrova. “The unfavorable effect of high doses of vitamin A persists even after stopping its use, depending on the drug - from 1 month to 2 years.”
How to use retinol cream for pigmentation
- Buy a cosmetic product, not a pharmacy form. Cosmetic products contain retinol of natural origin, rather than a synthetic analogue, are better tolerated and contain a number of additional ingredients with a brightening and soothing effect.
- Strictly follow the regimen of using the product; the frequency of use depends on the form and % content of retinol.
- Apply the product only to areas of pigmentation (if the spots are localized).
Don't forget to apply protective medications in the morning!
What is vitamin E
This is a family of tocopherols and tocotrienols - eight antioxidants that protect body cells from free radicals. This is the name given to oxygen atoms that are missing one electron. They strive to take it away from everything they reach, damaging surrounding cells and causing their death. Vitamin E absorbs free radicals, reducing the harmful effects of solar radiation and improving antitumor protection.
Getting into skin cells, it reduces the synthesis of prostaglandins and nitrogen oxides - mediators of inflammation. Its wound healing properties are known. Therefore, vitamin E is used to treat inflammatory skin diseases - psoriasis, atopic dermatitis, ulcers and pustular dermatosis. The anti-inflammatory effectiveness of tocopherol for acne has been proven. A study on mice showed that tocopherol prevented skin cancer, but this did not work in humans.
The magical effects of vitamin E are the result of taking it orally. When used externally, it does not treat wounds, burns and scars - this is what the study showed. But in combination with retinol, phytonadione and vitamin C, it sometimes helps remove circles under the eyes. It is often added to anti-aging creams, but it is not yet clear whether it will help protect skin from aging. But it is known that in some people the external use of this vitamin causes an adverse reaction in the form of contact dermatitis.
Should I take vitamin E supplements?
If a person eats more or less normally, he needs 4 years of extreme diet to use up all the vitamin E reserves in the liver. Therefore, tocopherol deficiency is rare. It usually appears if a person has impaired lipid absorption.
“Without fats, normal absorption of vitamin E is impossible, so it is important to include oils in your daily diet,” explains Nadezhda Nabatnikova. — Wheat germ oil, sunflower oil, safflower oil and soybean oil are rich in vitamin E. Nuts such as almonds and peanuts are also suitable sources.”
Only your doctor can decide whether you should take vitamin E supplements. If you self-medicate and drink “for health”, you can get hypervitaminosis. It is manifested by nausea, vomiting, weakness, headache and blurred vision. Particularly persistent ones lead themselves to disorders of the blood coagulation system.
Important to remember
- Vitamins A and E are fat soluble. They accumulate in the liver and enter the tissues that need them. Fats are needed not only for their preservation, but also for absorption
- Vitamin A is needed by humans for normal vision, skin condition, and even fetal development in a pregnant woman.
- A lack of vitamin A affects not only appearance, but also vision. If hypovitaminosis is not treated in time, you can go blind
- Systemic retinoids should not be taken during pregnancy - they cause serious fetal malformations
- Vitamin E is an antioxidant that protects the skin from free radicals
- Most people are not at risk of vitamin E deficiency. But hypervitaminosis with a tendency to bleeding is easy.
What if it's not enough?
Vitamin A deficiency disrupts the functioning of almost all body systems, and primarily affects appearance
.
The skin becomes drier and begins to peel, wrinkles appear on the face and hands, and dandruff appears in the hair. But the most well-known symptom of retinol deficiency is “ night blindness
,” that is, decreased vision in twilight or low-light conditions.
This condition is especially dangerous for those who have to spend a lot of time driving. Retinol deficiency also causes other vision-related symptoms. Due to deterioration in the formation of tear fluid, a feeling of “sand” appears in the eyes, redness and itching of the eyelids. This is the so-called dry eye syndrome. Men may notice a lack of this vitamin in the form of weakened erections
and premature ejaculation.
Frequent respiratory diseases
and serious decrease in working capacity are also signs of vitamin A deficiency.
