Vitamin A (retinol) is an essential micronutrient for all vertebrates. It is required for normal vision, reproduction, embryonic development, cell and tissue differentiation, and immune function.
Many aspects of the transport and metabolism of vitamin A, as well as it functions, are well conserved among species. Dietary vitamin A is ingested in two mainforms—preformed vitamin A (retinyl esters and retinol) and provitamin A carotenoids (b-carotene, a-carotene, and b-cryptoxanthin)—although the proportion of vitamin A obtained from each of these form varies considerably among animal species and among individual human diets. These precursors serve as substrates for the biosynthesis of two essential metabolites of vitamin A: 11-cis-retinal, required for vision, and all-trans-retinoic acid, required for cell differentiation and the regulation of gene transcription in nearly all tissues.Research on vitamin A now spans nine decades. Over 34,000 citations to vitamin A, 7,000 to b-carotene, and 20,000 to retinoic acid can be found in the National Library of Medicine’s PubMed database [1], covering topics related to nutrition, biochemistry, molecular and cell biology, physiology, toxicology, public health, and medical therapy. Besides the naturally occurring forms of vitamin A indicated earlier, numerous structural analogs have been synthesized. Some retinoids have become widely used as therapeutic agents, particularly in the treatment of dermatological diseases and certain cancers.
Function of vitamin A
Vitamin A serves a few significant jobs in the body:
1. Vision: Vitamin A is fundamental for keeping up with solid visual perception, especially in low light circumstances. It likewise forestalls night visual impairment and dry eyes.
2. Safe framework: Vitamin A assumes a significant part in supporting the resistant framework by assisting with warding off diseases and sicknesses.
3. Skin wellbeing: Vitamin A is significant for keeping up with solid skin by managing cell development and forestalling skin conditions like skin inflammation and psoriasis.
4. Development and improvement: Vitamin A is important for the development and advancement of bones, teeth, and tissues, including fetal advancement during pregnancy.
5. Cell reinforcement: Vitamin A goes about as a cell reinforcement, safeguarding the body from harm brought about by free extremists, which can add to constant illnesses like malignant growth and coronary illness.
Sources of Vitamin A
1. Orange and yellow fruits and vegetables including sweet potatoes, carrots, pumpkin, and mangoes.
2. Liver and organ meats from animals, such as beef liver, chicken liver, and kidney
3. Leafy green veggies like broccoli, spinach, kale, and collard greens
4. Dairy goods including butter, cheese, and milk
5. Fish including trout, salmon, and tuna
6. Breakfast cereal with added nutrients and other fortified meals
7. Eggs
8. Cod liver oil
