Vitamin A is important for good eyesight, healthy skin and and a strong immune system. Vitamin A also plays a role in growth and healthy reproduction. Because vitamin A comes in two forms, the term is sometimes used interchangeably with beta carotene, but technically, they are slightly different nutrients. There are other carotenoids too, but they are less studied than beta-carotene.

Preformed vitamin A comes from animal sources such as liver, cod liver oil, eggs and butter and can also be found in fortified milk products and breakfast cereals. This is the form that is used most efficiently by the body,  however, it is a fat-soluble vitamin and can become toxic when taken in excess, so getting the correct amount is important. More is not necessarily better in this case.

Provitamin A, or carotenoids such as beta-carotene, are found in dark green leafy vegetables and orange-colored vegetables. Beta carotene has to be converted in your body to make vitamin A. This makes it more difficult to overdose on beta carotene however, high doses from supplements, especially for smokers, may increase the risk of lung cancer. This is another example of why it is good to check with a registered dietitian nutritionist before starting a supplement.

Low intakes of vitamin A can result in night blindness. In ancient Egypt, night blindness was cured by eating liver, which is a rich source of this important nutrient. Vitamin A deficiency rarely happens in the U.S. anymore but can sometimes be found in people who have malabsorption issues such as diarrhea, Celiac disease, Crohn’s disease and pancreatic disorders. It may also happen as nutrient absorption decreases with increasing age.

Children living in poverty and people who drink excess alcohol are at risk as well. Vegetarians who do not consume eggs and dairy foods need to get at least five servings of fruits and vegetables daily, concentrating on those rich in beta- carotene, in order to meet their vitamin A needs.