Why Do We Need Vitamin A?
Vitamin A is a fat-soluble vitamin essential to our health. It helps us see normally in the dark. Vitamin A also promotes normal growth and health of body cells and keeps skin healthy.
There are animal sources (retinol) and vegetable sources (carotenoids) of vitamin A in foods. Only a few of the carotenoids in foods are converted to vitamin A in the body. Beta-carotene is the most familiar carotenoid.
Beta-carotene, like several other carotenoids, acts as an antioxidant. Antioxidants help slow or prevent cell damage.
By protecting cells from damage, antioxidants may reduce risk for certain cancers and heart disease.
What Happens If We Don’t Get Enough Vitamin A?
Inadequate intake of vitamin A can cause night blindness, dry, scaly skin, increased risk for infections, and poor growth.
How Much Vitamin A Do We Need?
Recommended intakes for vitamin A are given as “Retinol Activity Equivalents (RAEs).” Using RAEs helps account for the difference in activity between carotenoids and retinol. It takes about 12 units of beta-carotene or 24 units of other carotenoids to make 1 unit of retinol in the body.
Table 1. Recommended daily intakes of vitamin A
How Can We Get Enough Vitamin A?
We get vitamin A by eating a variety of fruits and vegetables that contain carotenoids and from dairy products fortified with vitamin A. Vitamin A also is found in liver and egg yolks.
What About Supplements?
We don’t need supplements because vitamin A is so widely available in foods and is easily stored in the body. Pregnant women especially should avoid taking retinol supplements. High doses during pregnancy can cause birth defects. Look for beta-carotene as the only vitamin A source in prenatal supplements.
How Much Is Too Much?
Taking large doses of retinol can cause nausea, vomiting, headaches, and dry, scaly skin. More severe health problems from storing excess vitamin A in the body are liver damage, osteoporosis, and nervous system disorders. Vitamin A toxicity can kill you! Keep your total vitamin A intake less than 3,000 μg per day from retinol.
Where Can I Get More Information?
The Family and Consumer Sciences (FCS) agent at your local UF/IFAS Extension office may have more information or nutrition classes for you to attend (find your local office at http://solutionsforyourlife.ufl.edu/map). Also, a registered dietitian (RD) can provide reliable information.
1. This document is FCS8639, one of a series of the Department of Family, Youth and Community Sciences, UF/IFAS Extension. First published: June 2001.
Latest revision: July 2013. Please visit the EDIS website at http://edis.ifas.ufl.edu.
2. Nan C. Jensen, MS, RD, UF/IFAS Extension Pinellas County, and Linda B. Bobroff, PhD, RD, LD/N, professor, Department of Family, Youth and Community Sciences; UF/IFAS Extension, Gainesville, FL 32611.
The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A&M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, Dean.