Vitamin A is a fat soluble vitamin, which means it is absorbed along with fats in the body and can be stored in the body’s liver and fatty tissue. Other types of fat soluble vitamins include Vitamin D, E and K. Your body doesn’t need fat soluble vitamins every day so they can be stored and used when you need them .
Vitamin A helps keep your heart, lungs and kidneys working effectively. It also helps with vision, immune and reproductive systems and helps with bone and tooth development. Most humans can get adequate amounts of Vitamin A through their diets by eating a variety of foods. There are two types of Vitamin A, ‘fully formed’ Vitamin A, which is found in meat, poultry, eggs and dairy products and the second type known as precursor or provitamin A which is found in fruit, vegetables and other plant-based products. Beta-carotene is the most common type of precursor of vitamin A which is found in foods such as dark leafy greens, sweet potato, carrots, broccoli and apricots. 
Most people can get sufficient amounts of Vitamin A in their diets but some people are deficient in Vitamin A and therefore need to supplement. Over supplementation can cause toxicity in the body so it is important to be aware of the recommended daily intake.
Vitamin A is added to many beauty and anti-aging products for its benefits in helping with certain skin conditions like acne, fine lines and wrinkles, clogged pores and fading age spots. Vitamin A retinoids have anti-inflammatory properties which can be beneficial for skin conditions. 
A study was conducted on 80 patients aged from 19 – 65 years old who were divided randomly in two groups. Group A received eye drops containing lubricant and topical vitamin A, this eye drop was given to patients as one drop in each eye every 4 hours during the waking hours for 6 months. Group B received topical lubricant eye drops used as one drop in each eye every 4 hours during the waking hours and oral vitamin A in the form of a capsule given once daily for 6 months. The study found that the oral Vitamin A antioxidant was much more effective and has a lasting effect much longer than the topical one. It is now recommended to consider oral vitamin A to relieve symptoms of dry eye syndrome. 
A vitamin A deficiency in children can lead to a greater risk of illness and death due to respiratory tract infections  Supplementation with Vitamin A has shown to reduce the risk of death in children aged 6-59 months old by 23-30% . Vitamin A supplementation has been shown to potentially speed recovery, reduce the severity and prevent subsequent episodes of acute lower respiratory tract infections .
Vitamin A plays an integral role in the human retinal pigment epithelial cells . A systematic review and meta-analysis of supplementing Vitamin A, Vitamin C and Vitamin E combined had positive outcomes and a larger effect on the reduction of age related macular degeneration than the individual vitamin . Vitamin A can be helpful for AMD if it is paired with other vitamins like Vitamin C and Vitamin E.
It is important to remember that Vitamin A is fat soluble which means the body will store excess amounts primarily in the liver. Over supplementation can cause toxicity in the body so it is important to be aware of the recommended daily intake.
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 Fawzi W, Mbise RL, Fataki MR, Herrera MG, Kawau F, Hertzmark E, et al. Vitamin A supplementation and severity of pneumonia in children admitted to the hospital in Dar es Salaam, Tanzania. American Journal of Clinical Nutrition. 1998; 68:187–192.
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