Vitamina A (Retinol)
In this article we are going to present all the information about vitamin A, the benefits, recommended daily dose, prospectus, overdose, foods that we can buy and many others.
Vitamin A was discovered in 1913, but only in 1947 did doctors manage to reproduce it in the laboratory.
It is one of the vitamins that play an important role in vision, especially in low light conditions, and for healthy skin and it is a fat-soluble vitamin, that is, soluble in fats, it dissolves in fats, not in water like most of micronutrients: vitamins and mineral salts.
It is also known as retinol, due to the fact that it produces pigments in the retina of the eye. It is also a great aid in the growth of bones, teeth, the maintenance of a healthy immune system and is a powerful antioxidant that fights diseases and maintains the health of the reproductive system.
Retinol is an active form of this vitamin and is found in the liver of animals and dairy products.Carotenoids are pigments that give color to egg yolks, tomatoes, mushrooms, all green leaves, fruits and flowers.
Beta-carotene is one of the more than 600 carotenoids found in nature. It is a powerful antioxidant that protects against free radicals (they contribute to the amplification of cornice diseases and have a significant role in the aging process).
Beta-carotene can also reduce the risk of developing cancer.For the first time in 1913 two biochemists from the University of Wisconsin discovered vitamin A and two other researchers, from Yale University, were able to synthesize it in 1947.
Benefits of Vitamin A in the body. What is it for?
A sufficient amount of vitamin A ensures the proper functioning of the whole body. It is necessary for the production of rhodopsin – a pigment responsible for twilight and night – and supports healthy skin, nails and teeth.
Vitamin A has an antioxidant effect, keeps cholesterol levels under control and helps us store fat. At the same time it protects the oral and digestive mucosa, but also takes care of the respiratory system.
It contributes to the development of bones, supports the immune system and helps us to heal more strategy in case of infections or inflammations.
That is why doctors prescribe it in cases of measles, for a faster recovery and to reduce the risk of complications.
Benefits and bodily functions of vitamin A we mention:
- Strong antioxidant effect;
- Protects against infections;
- Essential for good eye health;
- Protects the skin while maintaining its elasticity;
- It helps us assimilate calcium;
- Supports vision, especially night vision;
- Take care of the health of the nails and the dermis;
- Supports the formation of white blood cells;
- Supports the digestive system;
- Supports the reproductive system;
- Helps in the formation of antibodies and supports the immune system;
- Prevents anemia and favors the growth of children;
- Supports the development of strong bones, healthy hair, teeth and gums.
Good sources are: carrots and carrot juice which contains 1,692 mg of vitamin A, and 71 calories, while half a cup of cooked carrots contains 671 milligrams and just 27 calories). Cream of spinach (contains 573 mg of vitamin A and only 30 calories) and a salad bar.
Necessary daily intake of vitamin A
The required daily intake is calculated according to the age group:
- The necessary daily intake of for babies needs, daily, 350 micrograms of vitamin A.
- The intake increases to 400 micrograms for children between the ages of 1 and 3 years. 450 micrograms is the daily requirement for a 4-6 year old child. For the age group from 7 to 9 years the intake increases to 500 micrograms, and for the group from 10 to 12 years to 550 micrograms;
- Necessary daily intake for adolescent girls – 13 to 19 years of age need to eat 600 micrograms of vitamin A per day;
- Daily intake of necessary for adolescents-children – from 13 to 15 years of age need 700 micrograms a day, while children from 15 to 19 years of age, 800 micrograms;
- Necessary daily intake for adults-women s-600 micrograms;
- Daily intake of for adults-men -800 micrograms;
- Necessary daily intake for the elderly (over 75 years) – women -600 micrograms;
- Daily intake of for the elderly (over 75 years) – men -700 micrograms;
- Daily Intake Needed for Pregnant or Lactating Women – Pregnant women should take 700 micrograms of vitamin A from their daily diet, while lactating mothers need 950 micrograms.
Foods with vitamin A for Vegetarians and Vegans
Vitamin A is found naturally in foods of animal origin, such as eggs, liver, fish (anchovies, mackerel), milk, and dairy products, such as sour cream or butter.
A vegan diet simply does not provide the body with adequate vitamin A for optimal health.
A vegan diet also reduces thyroid function and bile release, drastically compromising the poor conversion of carotene to cartenoid.
A vegetarian may be able to meet daily vitamin A requirements by emphasizing egg yolks and dairy products. If I could suggest a meat-based product for a vegetarian to consume, it would be dried liver capsules.
Vitamin A is found especially in green vegetables and fruits – spinach, lettuce, lemon, grapefruit – or orange-mango or carrots.
The liver is the best source of vitamin A and the most nutrient-dense food.
Effects of vitamin A on the body:
Besides the clear benefit for vision, it also has many other properties that benefit the human body. This is extremely necessary in children’s nutrition , as it helps them develop their bones and teeth.
The Vitamin A is also needed in: reproductive function, maintaining healthy skin, gums and mucous membranes, protecting the body against infection.
Diseases that can occur due to vitamin A deficiency:
Vitamin A deficiency is a real problem in developing countries. Some 500,000 children up to 5 years of age end up losing their sight or even their lives, due to a lack of vitamin A or fat in which it is soluble.
Other effects in children: respiratory infections, diarrhea and retardation, even stop, growth, due to the cumbersome development of the bones.
Lack of vitamin A, or its deficiency, makes our body much more vulnerable to infection, which is why a large number of microbes or viruses, in a body that is deficient in vitamin A, are stronger.
Recommended daily dose and excess Vitamin A
What is the average daily minimum requirement for vitamin A and when can overdose occur?
Recommended daily dose:
- Children over 10 years of age and people under the age of 18: 0.8 mg
- Adolescent girls: 1 mg
- Women: 0.8 mg
- Pregnant women: 1 mg
- Women during lactation: 1.3 mg
- Men: 1 mg
As can be seen, vitamin A is very important for each age group, but more important for pregnant women and women who breastfeed, for them the daily need for vitamin A is higher.
Overdose or excess of vitamin A
May be harmful if exceeded for several months (recommended daily dose). Therefore, in men, 1.5 mg administered for several months can produce toxic effects, while in children, during a similar period, the daily administration of 0.55 mg, can produce adverse effects.
Adverse effects, vitamin A overdose, symptoms
Among the symptoms of administration, for a period of a few months, at a daily dose higher than the recommended daily dose are: hair loss, nausea, vomiting, acne, impaired vision, irregular periods, fatigue, liver enlargement, or pain in the head.
Foods rich in vitamin A
In its natural state it is found in various foods such as: carrots, Kapia peppers, bell peppers, red beets, tomatoes, lettuce, butter, cheese, etc.
Do not forget that this vitamin is fat soluble, so if you eat a diet where it is not found in, vitamin A will not be able to be absorbed by the body.
In some countries where rice consumption is very high, due to vitamin A deficiency, scientists have started to work on genetically modified rice, rich in beta-carotene, 20 times more than normal rice.
This project was funded from the beginning by the Rockefeller Foundation, the Swiss Federal Institute, but also by the European Union, one of the main testing centers being the Philippines.
Vitamin A is found in most multivitamin compounds, but it can be found separately in the form of ampoules, tablets (pills), oil, drops etc.
Our recommendation is that each of you take the necessary intake, respecting a healthy lifestyle and eating foods rich in vitamin A.
Vitamin A deficiency in the body
Vitamin A deficiency is one of the main causes of vision loss, that is, reduced visual acuity in the dark. Other signs may include slowed growth in children or reproductive problems in adults.
Dry skin, frequent infections, and gingivitis can be related to a vitamin A deficiency. Severe vitamin A deficiency can cause severe anemia or even death.
Symptoms of a lack of vitamin A
The most serious symptoms of a lack of vitamin A are:
Decreased visual acuity: If diopters vary greatly from year to year, you may have a vitamin A deficiency in your body. This vitamin is essential for all the functions of the eye. Also, in his absence we could not see.
Among the first symptoms of eye problems caused by a lack of vitamin A are the sensation of itching in the eyes, burning sensation and swelling of the eyelids.
● Problems with the digestive system-in the absence of optimal amounts of vitamin A, your digestive tract is dry, the secretion of digestive juices is significantly reduced. Therefore, it increases the risk of intestinal infections and diarrhea;
● Appearance of Aged Skin – Vitamin A deficiency causes dry skin, which becomes rough and flaky. Furthermore, the lack of optimal vitamin A intake causes thickening of the keratin layers on the palms of the hands and soles, and the skin on the arms, thighs and buttocks has the appearance of “chicken skin”;
● Respiratory tract infections in the absence of a sufficient amount of vitamin A in the body, nose, throat, or bronchial tubes become dry and hard, breathing undergoes a serious infection;
● Diseases of the reproductive system, a low intake of vitamin A can lead to metaplasia (the transformation of morphological and functional tissue) at the level of sexual splendor, bladder, pelvis, etc. In women it can cause vaginitis;
Vitamin A deficiency during pregnancy – A severe vitamin A deficiency during pregnancy can lead to miscarriage.
Risk factors for vitamin A deficiency
Among the risk factors that can lead to a deficiency is vitamin A in the body:
Alcohol use – we are talking about the abuse of alcohol, which leads to deficiencies of vitamin A, and zinc, and cause a number of disorders in the body, including loss of sense of smell and smell, sexual dysfunction, or nyctalopia (blindness night, in Japanese terms, or dazzling at night).
Fighting the deficit will alleviate these symptoms; Poor nutrition-the most common cause of vitamin A deficiency is malnutrition. Vegetarians or people who eat little meat and animal products are most at risk;
Lack of breastfeeding: breast milk is the most important source of vitamin A for infants. Children who are not breastfed are at greater risk of developing a vitamin A deficiency;
Pregnancy-a deficiency can occur and during pregnancy, due to which the body of a pregnant woman consumes a greater amount of vitamins and minerals. A diet rich in vegetables and fruits is recommended.
Dietary supplements are taken during this period only on the recommendation of the doctor, since vitamin A can cause congenital malformations of the fetus.
Prevention of vitamin a deficiency
The best method to prevent a vitamin A deficiency is a balanced diet, from which liver, dairy, green, yellow and orange fruits and vegetables are not lost.