A Comprehensive Review: The Role of Vitamins in Human Diet I. Vitamin A-Nutrition

From this review, it is very clear that vitamin A ingested as a provitamin (carotenoid) from vegetable food or as retinol palmitate from animal sources, can play a vital role in human nutriture. It is important for cell growth and cell differentiation, its deficiency leads to metaplasia of the respiratory, gastrointestinal and genitourinary tracts. An appreciable quantity of this vitamin in the diet is essential. It was observed that vitamin A in dehydrated foods is readily destroyed in the presence of oxygen, moisture, sunlight, mineral matter and temperature which lead to deficiency of vitamin A in the diet of most of the Asian populations. Therefore, an appropriate amount of vitamin A must be fortified to the staple diet according to the RDA level in order to avoid various serious complications in man, particularly among preschool children and pregnant women.