What the research says

Research on vitamin A taken by mouth, also called oral vitamin A, for specific conditions shows:

• Acne. Large doses of oral vitamin A supplements don't seem to affect acne.
• Age-related macular degeneration. A large clinical trial showed that people at high risk of advanced age-related macular degeneration lowered their risk of developing the condition by taking a specific combination of vitamins that included beta-carotene. It's not clear what role beta-carotene played.
• Cancer. Some research studies suggest that people who eat a diet high in vitamin A may lower their risk of cancers of the pancreas, ovaries and food pipe, also called the esophagus. The connection between use of vitamin A supplements and lowered risk of cancers of the liver, colon, rectum and prostate and other types of cancer isn't clear.
• Heart disease. Vitamin A is an antioxidant, but research hasn't shown that taking vitamin A supplements helps prevent heart disease.
• Measles. Children with low vitamin A levels who get measles are more likely to be very sick than are children with recommended levels. Vitamin A supplements do not prevent measles. Getting a measles vaccine is the most effective and safest way to prevent measles. Don’t give vitamin A to children as a treatment or supplement unless a healthcare professional recommends it. Only take the recommended amount. Taking too much vitamin A can cause major harm.
• Vitamin A deficiency. People who have low levels of vitamin A, called vitamin A deficiency, seem to benefit most from vitamin A supplements. This kind of deficiency is rare in the United States. Vitamin A deficiency causes anemia and dry eyes.

Beyond use as a supplement taken by mouth, vitamin A is used in creams put on the skin to lessen fine wrinkles, splotches and roughness and treat acne.