Vitamin A is medically known as the ‘retinol’. It is stored in the liver and maintains healthy bones, teeth and especially soft tissues as we have them in our eyes. It also protects mucus membrane that line important organs such as nose, mouth, lungs and throat from various infections. The word ‘retinol’ is given since Vitamin A produces the pigments that are essential for working of the retina and they are also helpful to maintain a normal and clear vision. It is therefore, deficiency of Vitamin A can lead to weak eyesight and in severe cases, the night-blindness. Retinol is a fat soluble Vitamin and is required to assure proper functioning of the immune system of the body.
The main source of Vitamin A is from animal; however, its precursor form (called as beta-carotene or a provitamin A) can be found in plants that have typical colors like dark green as in vegetables and bright color as in fruits and other vegetables like carrots, sweet potatoes and beet roots etc. Since retinol is a fat-soluble Vitamin, it gets dissolved and remains in the adipose tissues (fats). In short, it can remain in the body and unlike other Vitamins, do not get excreted by body in any way. They are required in little quantity and hence, Vitamin A, if consumed in excess, can produce toxic reactions in the body.
A precursor of Vitamin A, beta-carotene carries antioxidant properties and hence, it helps dealing with unstable chemicals such as free radicals that are known for their ‘cell destructive’ capacity. Free radicals are by-products of the body while the process of metabolism is going on. They continuously get produced and over the times, when the amount of such radicals become significant, they start troubling body systems and then they increase the potential for hurt to the bodily tissues. Precursor of retinol can help reducing the production of free radicals and neutralize them that are already present in the body and the body is prevented from major health ailments such as cancer, heart disease, inflammatory conditions and other autoimmune diseases.
Other knock-on effects of Vitamin A include proper tissue growth and repair, healthy skin, protection against airborne infections and pollutions, strengthening bones and teeth, preventing certain oral cancers (up to some extent), counteracting night-blindness and weak eyesight. Some health experts agree that retinol can also help in rejuvenating the entire reproductive tract along with its organs.
Vitamin A (retinol) is available in abandon quantity in kale, fish liver oil, spinach, carrots, and broccoli and in liver. Fortunately, we can also supply Vitamin A from outside. Vitamin supplements such as pills, syrups and powder can be fortified with Vitamin A and is prescribed in certain dosage for certain period.
The current Recommended Dietary Allowance (RDA) for Vitamin A in North America is 5000 IU (more accurately – 1000 RE) for men and 4000 IU (more accurately – 800 RE) for females. The children require about 400-700 RE. Vitamin A, if taken in excess quantity, can produce some hazardous conditions; for instance, an excess quantity of vitamin A can produce liver toxicity