WHAT IS VITAMIN A?
Vitamin A is the common name for a group of essential ingredients that are important for vision, bone growth, cell division, reproduction, and cell differentiation (when a cell separates from tissue, such as in the lungs).
WHICH FOODS CONTAIN VITAMIN A?
Vitamin A can be found in foods we get from animals, such as eggs, milk and liver. In many cases, vitamin A is added to skim milk, as it is lost when fat is derived from milk.
Most vitamin A from foods of animal origin is found in beef, chicken, milk, cheese and eggs. Most sources of vitamin A are found in plants such as carrots, spinach, carrot juice, vegetable soup, spinach, melons, apricots, papayas, mangoes and peas.
WHAT TYPES OF VITAMIN ARE THERE?
There are two types of vitamin A, depending on the food as the source from which it comes - animal or plant. Vitamin A derived from animals is called preformed vitamin A. It is absorbed from retinol, one of the most active forms of vitamin A. Vitamin A found in fruits and vegetables is called provitamin A carotene. Both types of vitamin A are converted to retinol within our body. In the United States, 34% of vitamin A is consumed by women in the form of provitamin A carotene, while in men it is 26%.
WHAT IS THE FUNCTION OF VITAMIN A?
Vitamin A helps the body regulate the immune system, thus preventing or fighting infections by producing white blood cells. Vitamin A is also thought to help lymphocytes prevent and control infections more effectively. Vitamin A improves vision and helps the respiratory organs, urinary and digestive tracts. When the body is under great strain, bacteria are much easier to penetrate our bodies and cause infection. Vitamin A helps our skin and mucous membrane function, thus protecting our body from bacteria and viruses.
- strengthens bones, joints and muscles
- fights and prevents diseases and infections
- helps maintain healthy eyesight (especially night vision)
The recommended dose of vitamin A for adult men is 900mcg, and for female adults 700mcg.
WHO HELPS VITAMIN A SUPPLEMENTATION?
Everyone should take vitamin A, especially people of African and Latin American descent. These two groups of people are at risk of developing vitamin A deficiency in the body, especially when vitamin A is not ingested in sufficient quantities. Some of the signs of a deficiency of this vitamin in the body are deterioration of night vision, dry skin and hair, inflamed skin, uneven bone development and defective tooth glaze. In pregnant women, unhealthy embryos may be associated with vitamin A deficiency.
DOES VITAMIN A HAVE NEGATIVE EFFECTS?
If not taken in excessive amounts, vitamin A does not cause adverse effects. When taken excessively, so-called hypervitaminosis A if excessive amounts of pre-formed vitamin A (vitamin A of animal origin) are ingested. Since vitamin A is absorbed at a rapid rate in the body, and relaxes very slowly, you must be careful not to take too much of this vitamin in a short period of time. Toxicity is rare, but its symptoms include nausea, headache, fatigue, loss of appetite, dizziness, dry skin, and cerebral edema.