The first vitamin discovered, vitamin A, is evident in the natural coloring of foods: the brilliant red in a pepper, the deep orange in a carrot or the golden yellow hues in squash. Sometimes the color of vitamin A is masked by a deep green color, so it can be found in some leafy green vegetables too.
What Is It? Vitamin A is a family of fat-soluble nutrient compounds called retinoids that are stored in your liver. Vitamin A is found in two forms: preformed vitamin A, also called retinol, is found only in animal foods. Provitamin A, or beta-carotene, is stored in plant foods. Vitamin A is best absorbed in the presence of some dietary fat.
Why You Need It
Bones & Teeth
Growth and development of teeth and bones depend on an adequate supply of vitamin A, especially during infancy and the years of rapid growth.
Vitamin A helps stimulate the immune system to line your air passages and digestive tract with protective cells that resist infection. Optimal intakes of vitamin A may strengthen the immune system and fend off certain cancers. Vitamin A helps protect body surfaces designed to keep infection and disease out. These special surfaces include your skin and the moist lining of your mouth, throat and digestive tract. Vitamin A?s influence on immunity may be one of the ways it helps prevent the initiation or growth of cancer cells.
Skin & Hair
Vitamin A is essential for normal growth and healthy development of all body tissues and helps maintain the protective layers of your skin, especially the eyes.
Vitamin A combines with a special protein in your eye to improve night vision and aid color perception. Night blindness is the slow recovery of vision after bright flashes of light in the dark. Bright light bleaches eye pigments that are normally regenerated by retinal in the eye.
Children 1-3: 300 mcg/d
Children 4-8: 400 mcg/d
Children 9-13: 600 mcg/d
Adults 14+: Men 900 mcg/d, Women 700 mcg/d
Pregnant Women: 770 mcg/d
Best Natural Food Sources
- Sweet Potatoes
- Turnip Greens
If You Get Too Little
Signs of vitamin A deficiency include poor night vision, decreased resistance to infection, extremely dry skin and dull hair. In children, mild vitamin A deficiency may increase a child?s risk for respiratory infection and decrease growth rates, bone development and the likelihood of survival from serious illness. Xerophthalmia is the deficiency disease that results from too little vitamin A. When the mucous membranes in the eye dry out, small particles of dirt may settle there. Bacteria can enter the vulnerable eye through scratches caused by these dirt particles. White blood cells, which help fight infection, start attacking bacteria in the scratches and cause lesions. As these lesions grow, blindness can result.
If You Take Too Much
Toxic level of vitamin A may cause blurred vision, diarrhea, headaches, irritability, muscle weakness, scaling or peeling of skin and vomiting. In growing children, excess vitamin A can cause premature bone closure that result in deformities. Too much vitamin A is also known to caused stunted growth in children. During pregnancy, vitamin A toxicity causes a variety of serious birth defects. Many prescription and over-the-counter acne medications contain high levels of vitamin A that should be avoided by women who may become pregnant. The minimum toxic dose of vitamin A is 6,500 IU per day.
Remember: The more intense the color of the fruit or vegetable, the higher the vitamin A content. Look for deep yellow or orange.
Increase your intake by eating these foods rich in vitamin A:
- Add spinach leaves to salads and sandwiches.
- Add pureed carrots to soup.
- Add a sweet potato to the white potatoes in your favorite mashed potato recipe.
- Add grated carrots to meatloaf.
- Top hot or cold cereal with dried apricot bites.
- Try carrot-based juices.
- Add fresh peppers to salads and pasta dishes.