How many vitamin a

Get the latest public health information from CDC. Have a question? This is a reader-friendly overview of Vitamin A.

For more details, see our health professional fact sheet on Vitamin A. Vitamin A is a fat-soluble vitamin that is naturally present in many foods. Vitamin A is important for normal vision, the immune system , and reproduction. Vitamin A also helps the heart, lungs, kidneys , and other organs work properly. There are two different types of vitamin A. The first type, preformed vitamin A , is found in meat, poultry, fish, and dairy products.

The second type, provitamin A, is found in fruits, vegetables, and other plant-based products. The most common type of provitamin A in foods and dietary supplements is beta-carotene. The amount of vitamin A you need depends on your age and sex. Average daily recommended amounts are listed below in micrograms mcg of retinol activity equivalents RAE. Vitamin A is found naturally in many foods and is added to some foods, such as milk and cereal. You can get recommended amounts of vitamin A by eating a variety of foods, including the following:.

Vitamin A is available in dietary supplements, usually in the form of retinyl acetate or retinyl palmitate preformed vitamin A , beta-carotene provitamin A , or a combination of preformed and provitamin A. Most multivitamin-mineral supplements contain vitamin A. Dietary supplements that contain only vitamin A are also available. But a cup of non-fat milk contains only about IU mcg , and a serving of cereal about as much.

Try to get much of the extra vitamin A you need from the beta-carotene in yellow-orange vegetables and fruits carrots, tomatoes, cantaloupe and in deep-green vegetables such as spinach. And don't forget the other things that keep bones strong, including proper amounts of vitamin D and calcium, and lots of weight-bearing and resistance exercises.

From A to D, nutrition is getting more complex every year. In the case of vitamin A, though, it's also getting smarter. As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.

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Sign Up. Close Thanks for visiting. Tanumihardjo SA. Vitamin A: biomarkers of nutrition for development. Food and Drug Administration. Department of Agriculture, Agricultural Research Service. FoodData Central , Dietary supplement use in the United States, J Nutr ; What We Eat in America, World Health Organization. Geneva: World Health Organization; Vitamin A supplements for preventing mortality, illness, and blindness in children aged under 5: systematic review and meta-analysis.

BMJ ;d Vitamin A deficiency and clinical disease: An historical overview. Vitamin A and preterm infants: what we know, what we don't know, and what we need to know.

Vitamin A supplementation to prevent mortality and short and long-term morbidity in very low birthweight infants. Vitamin A supplementation for postpartum women.

Vitamin A supplementation during pregnancy for maternal and newborn outcomes. Elevated vitamin A intake and serum retinol in preadolescent children with cystic fibrosis. Am J Clin Nutr ; Vitamin A supplementation for cystic fibrosis. Consensus report on nutrition for pediatric patients with cystic fibrosis. J Pediatr Gastroenterol Nutr ; Nutrition management of pediatric patients who have cystic fibrosis.

Pediatr Clin North Am ; Effects of a combination of beta carotene and vitamin A on lung cancer and cardiovascular disease. N Engl J Med ; The effect of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers. Lack of effect of long-term supplementation with beta carotene on the incidence of malignant neoplasms and cardiovascular disease. The New England journal of medicine ; Dietary supplement use and prostate cancer risk in the Carotene and Retinol Efficacy Trial.

Cancer Epidemiol Biomarkers Prev ; Associations between alpha-tocopherol, beta-carotene, and retinol and prostate cancer survival. Cancer Res ; Serum retinol and risk of prostate cancer. Am J Epidemiol ; A randomized, placebo-controlled, clinical trial of high-dose supplementation with vitamins C and E, beta carotene, and zinc for age-related macular degeneration and vision loss: AREDS report no. Arch Ophthalmol ; JAMA ; Vitamin A for treating measles in children.

Cochrane Database Syst Rev ; Effectiveness of measles vaccination and vitamin A treatment. Int J Epidemiol ;39 Suppl 1:i Routine vitamin A supplementation for the prevention of blindness due to measles infection in children. Corneal ulceration, measles, and childhood blindness in Tanzania. Br J Ophthalmol ; Beta-carotene is an important vitamin A source for humans.

The Journal of Nutrition ;SS. The vitamin A content and toxicity of bear and seal liver. Biochem J ; Vitamin A: is it a risk factor for osteoporosis and bone fracture? Nutr Rev ; J Natl Cancer Inst ; Genentech USA, Inc.

Xenical Package Insert. Vitamin A is an essential nutrient that contributes to many functions in the body, such as protecting eye health. In the U.

Most people can meet their needs for vitamin A through their diet. In some cases, however, a doctor may recommend supplements. How long do vitamins last? Here, learn whether they expire and whether it is safe to take vitamin supplements after their expiration dates.

All vegetables provide key vitamins, minerals, and fiber, but some offer more health benefits than others. Learn about 15 of the most healthful…. Retinol can help reduce the appearance of wrinkles, acne, cellulite, and more. Learn about some of the best retinol creams available here.

New research has found that nutrients obtained from food, not supplements, correlate with lower risks of all-cause mortality and cancer. Vitamins are essential to human health. Here, learn about each of the 13 vitamins, including good sources and how they help. Learn more here. Types Benefits Sources Recommended intake Risks Summary Vitamin A is an essential vitamin that the body needs for growth and development. Food sources. Recommended intake.

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