Vitamin A, also known as retinol, is the first substance to be isolated among vitamins. It is a fat-soluble vitamin, and its derivative, retinol, is crucial for vision and skin. Further, vitamin A has critical immunity-boosting functions, and it helps maintain healthy bones, teeth, soft tissues, and mucous membranes.
Sources of Vitamin A
● Vitamin A is found in animal food sources rich in fat such as milk, cheese, yogurt, fatty fish, and liver.
● Precursors of vitamin A known as carotenoids are present in most red and green vegetables such as carrots, spinach, kale, sweet potato, and red and yellow bell peppers.
● Vitamin A is also found in fruits such as mango, cantaloupe, watermelon, and grapefruit.
Although carotenoids are fat-soluble, they are less toxic, even when consumed in large quantities, unlike their animal derivatives. The best-known carotenoid is beta-carotene. Both retinoids and carotenoids are good antioxidants and help in fighting multiple diseases caused due to free radicals.
On average, adult men need 700 µg, and women need 600 µg of vitamin A a day. Consuming too much (> 1500 µg) is not advisable and causes adverse effects, such as birth defects, congenital issues, and even bone defects like osteoporosis.
All consumable sources of vitamin A should be from regular food items. Supplements should only be taken if advised by a professional.
Role of Vitamin A in Growth, Development, and Immunity
● Integral part of cell growth and differentiation
It helps with the growth of sperm, one of the primary sources of life. It also aids the growth and nourishment of the fetus by helping the development of the placenta and other crucial tissue.
● Helps in the growth and development of epithelial cells
They are the ubiquitous components of the biological system. It includes the linings of mucous membranes, gastrointestinal tract, lungs, bladder, urinary tract, vagina, cornea, blood vessels, and skin. Vitamin A also maintains bone and tooth health. Further, it keeps the skin healthy and hydrated from within.
● Crucial micronutrient for vision
Retinol, a vitamin A metabolite, combines with opsin, a retinal pigment, to form rhodopsin. Rhodopsin is critical for night vision. It is also crucial for the growth, differentiation, and proper functioning of the conjunctival membranes and cornea.
● Protects against a host of diseases
It is scientifically proven to reduce morbidity and mortality in infectious diseases and conditions, including diarrhea, enteric infections, malaria, mumps, measles, and pneumonia.
● Critical immunity-building functions
Vitamin A has shown promise in reducing the severity of tuberculosis and acquired immunodeficiency syndrome (AIDS), reducing oxidative stress, and promoting a healthier immune system.
When taken in recommended amounts, vitamin A is a lifesaver. We suggest a balanced diet rich in green, red, yellow, and orange fruits and vegetables and animal food sources with regular exercise for a robust immune system and good overall health.