Vitamin A: Essential for Eye Health

Foods containing vitamin AWe all strive to eat well for optimal health and many of us choose to add supplements to our diets to ensure that all of our nutritional needs are being met. Multivitamins are the most popular supplement, used by 40% of all adults in the U.S. In fact, the word vitamin implies good health as its root vita means life. In taking a closer look at the essentials required for good eye health, one nutrient in particular stands out as one of the most critical:  Vitamin A. Vitamin A is actually comprised of a number of related compounds. The two main types are retinols and carotenoids. Retinols come from animal sources of food and are called “pre-formed,” meaning they can be used directly by the body. Carotenoids come from fruits and vegetables as “provitamin A” and are converted by the body into retinol.

Retinol is accumulated in the retinal pigment epithelial cells and plays a key role in the eye’s sensitivity to light. This light-sensitive pigment is present in both the rod and cone cells of the eyes. Vitamin A also helps to maintain epithelial cells. These cells form keratin to allow for the transparency of the cornea to let in light.

Although vitamin A deficiency is rare in the U.S., it is the leading cause of preventable blindness in developing countries according to the World Health Organization. One of the first signs of vitamin A deficiency can be night blindness. A lack of vitamin A has also been associated with the development of dry eyes. A condition called xerophthalmia, resulting from prolonged or severe vitamin A deficiency, causes changes in the cells of the cornea that can lead to corneal ulcers, scarring, and blindness.

Vitamin A is fairly easy to incorporate into your diet and is most often found in green and yellow vegetables. Some good sources of vitamin A include:

  • Spinach
  • Carrots
  • Kale
  • Sweet potatoes
  • Cantaloupe
  • Beef and chicken liver
  • Milk and cheese

As a treatment for eye conditions, researchers have found some successes in using vitamin A-containing eye drops to treat dry eye and incorporating adequate vitamin A in diets to slow the progression of age-related macular degeneration.

When planning meals or shopping for groceries, don’t forget to include green and yellow vegetables for good eye health.