Vitamin A is an antioxidant vitamin which has a great role in vision and skin health besides strengthening the immune system. Vitamin A helps the surface of eye and skin to become a protective barrier against invading bacteria and other germs. Thus it is useful in preventing eye infections, visual loss, and skin diseases.
Vitamin A is actually present in two forms depending on the type of food. When derived from animal source it is called retinol. It is a preformed vitamin A. The good source is animal liver, cheese, whole milk etc.
Vitamin A derived from plant source is in the form of carotenoids. Carotenoids are precursor of vitamin A. When plant food is ingested, our body converts these carotenoids into retinol. Beta carotene is one of the most useful and available carotenoids among its different types. The rich source of carotenoid is carrots, spinach, green leafy vegetables, kale etc.
Effect Of Vitamin A Deficiency On Eye Health
- Since vitamin A is necessary for good vision it has a vital role in keeping the eyesight healthy. Its deficiency can lead to dryness of conjunctiva and cornea, the outer layer of eye.It leads to a condition called keratoconjunctivitis.
- Deficiency of vitamin A can also lead to night blindness. Though this condition is rare in developed countries, it is still common in children residing in developing countries where malnourishment is common.
- Deficiency of vitamin A can affect the retina. The rods and cones in the retina require vitamin A for better functioning. Retina is situated in the posterior segment of eye. Its function is to create an image and send it to brain through optic nerve. Lack of vitamin A will affect the rods and ultimately the visual ability of the eye. Often macular degeneration at an early age is due to lack of vitamin A.
In most cases healthy and complete nutritious diet provides vitamin A in sufficient amount and there is no need for supplements containing vitamin A. The daily requirement of vitamin A is 5000 IU. However, patients who are suffering from night blindness may require more amount of vitamin A for few weeks.
In corneal damage the daily dose of 6000mcg per kg body weight for 5 days have proved beneficial. In cases of xerophthalmia, a type of dry conjunctivitis due to lack of vitamin A in very young children, 60,000 mcg of retinol can be administered orally in a single dose with beneficial results
Benefits Of Vitamin A For Healthy Skin
Vitamin A helps the skin to remain healthy and elastic. It supports the deeper layer of skin called dermis to remain strong and elastic. Collagen, elastin and blood vessels are situated in dermis. Elastin and collagen are proteins that keep the skin elastic. Thus sufficient amount of vitamin A prevents premature wrinkling. It is useful in rosacea. It also repairs the upper layer of skin and helps to heal the wound easily.
Vitamin A is beneficial in reducing hyper-pigmentation as it reduces clumping of pigments that give color to the skin. Vitamin A is also found beneficial in curing acne. Experts believe even stubborn acne condition is cured when adequate amount of food containing vitamin A is eaten. To cure stubborn acne, many times dermatologists recommend topical applications which contain vitamin A. Vitamin A is also beneficial in treating warts and other skin growths.
Tough we know the importance of vitamin A in our daily life, it is necessary to consult the physician before taking vitamin A supplements. This is because vitamin A taken in large amount for a prolonged period of time can lead to vitamin A toxicity. The characteristic features of toxicity are hair loss, loss of appetite, parched lip and weight loss.