Saturday, August 22, 2009
Food Sources of Vitamin A
Vitamin A sources can be classified as plant and animal food sources. Plant sources include both fruits and vegetables that contain vitamin A, while animal sources includes meat and poultry derived foods. Animal Sources: In animal foods, vitamin A is found as retinol, one of the most important forms of vitamin A, which is usually converted into retinal and retinoic acid. Some important sources of this include beef, chicken, eggs, fish, cheese and seafoods. Plant Sources: In plants, vitamin A is found as provitamin A carotenoids. Some important carotenoids are carotene (alpha and beta carotene) and cryptoxanthin. Apricot, cantaloupe, mango, orange, apple, watermelon, plum, blackberry, peach and kiwi are some of the fruits that contain vitamin A. Among the vegetables, carrot, pumpkin, broccoli, peas, spinach, sweet potato, turnip, tomatoes, wheat germ, escarole, collards, dandelion green, mustard green, aloe vera etc. are rich sources of vitamin A. However, cooking and storing of these vegetables and fruits may result in substantial loss of vitamin A. Therefore, it is very important to cover them while storing in refrigerators. Raw fruits and vegetables can provide more vitamins than cooked ones, so it is best to eat them raw. While cooking vegetables, it should be kept in mind that steamed or baked vegetables are more likely to retain the essential vitamins than the fried ones. Our bodies need certain essential minerals like zinc and iron for the proper utilization of vitamin A. Zinc is required for the transportation of vitamin A from the storage organ liver to the tissues, while this vitamin plays an important role in the metabolism of iron. Deficiency of vitamin A can trigger a number of diseases in human beings. Its deficiency usually results in night blindness, which can eventually lead to complete blindness. Deficiency of this vitamin can also weaken the human immune system. Studies have revealed that children with mild deficiency of vitamin A are at a greater risk of developing respiratory diseases and diarrhea. Studies have also shown that the presence of vitamin A can decrease the occurrence and severity of measles. So, including sufficient amount of vitamin A-rich foods in your diet, along with iron and zinc is an indispensable prerequisite for living a disease-free, healthy life.