RWJUH at Hamilton
SearchSite Map
Contact UsHelp
Medical Services Your Support Employment Patient/Visitor's Guide Directions

For a complete list of hospital classes and events, click here to connect to HealthConnection Online




Medical Encyclopedia

Encyclopedia -> Nutrition -> V -> Vitamin A

Vitamin A

Alternate Names: Vitamin A deficiency; Deficiency - vitamin A

Food Sources:

Vitamin A comes from animal sources such as eggs and meat, and is present in the form of a precursor called beta-carotene, when manufactured by plants.

Vitamin A is found in milk, cheese, cream, liver, kidney, cod and halibut fish oil. All of these sources, except for skim milk that has been fortified with vitamin A, are high in saturated fat and cholesterol. The vegetable sources of beta-carotene are fat and cholesterol free. The body regulates the conversion of beta-carotene to vitamin A based on the body’s needs. Sources of beta-carotene are carrots, pumpkin, sweet potatoes, winter squashes, cantaloupe, pink grapefruit, apricots, broccoli, spinach, and most dark green, leafy vegetables. The more intense the color of a fruit or vegetable, the higher the beta-carotene content.

Functions:

Vitamin A helps in the formation and maintenance of healthy teeth, skeletal and soft tissue, mucous membranes, and skin. It is also known as retinol because it generates the pigments in the retina.

Vitamin A promotes good vision, especially in dim light. It may also be required for reproduction and lactation. Beta carotene, which has antioxidant properties, is a precursor to vitamin A.

Recommendations:

Recommended daily allowances (RDAs) are the levels of essential nutrients that the Food and Nutrition Board judges as adequate to meet the known nutrient needs of almost all healthy persons.

The best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods from the food guide pyramid.

Side Effects:

Vitamin A deficiency can increase the susceptibility to infectious diseases, as well as cause vision problems.

Large doses of vitamin A can be toxic. They can also cause abnormal fetal development in pregnant women. Increased amounts of beta-carotene can turn the color of skin to yellow or orange. The skin color returns to normal once the increased intake of beta-carotene is reduced.

Disclaimer: The text presented on these pages is for your information only. It is not a substitute for professional medical advice. It may not represent your true individual medical situation. Do not use this information to diagnose or treat a health problem or disease without consulting a qualified health care provider. Please consult your health care provider if you have any questions or concerns.

Copyright © 1999-2001 Medical Network Inc. All rights reserved. No part of the contents of this web site may be reproduced or transmitted in any form or by any means, without the written permission of the publisher. "HealthAtoZ.com" should be prominently displayed on any material reproduced with the publisher's consent.