Vitamin A deficiency is uncommon in the U.S., but it affects many people in the developing world. One of first symptoms of a vitamin A deficiency is night blindness, which, if untreated can develop into full scale blindness. According to the World Health Organization Report on Vitamin A Deficiency, night blindness is estimated to affect 5.2 million preschool-age children and 9.8 million pregnant women around the globe.
Writing on a case in The Lancet, doctors who treated a pregnant woman who came to the emergency room after several weeks of progressive sight loss described this particular case, “Vitamin A deficiency can be secondary to poor intestinal absorption due to weight loss surgery, Crohn’s disease or pancreatic dysfunction. Our patient had anorexia nervosa and had limited her diet to white onions, white potatoes, and red meat for the past 7 years.”
We usually recommend taking vitamin A in the form of beta-carotene, which converts to vitamin A with a small amount of fat in the diet. Food sources of vitamin A include: yellow and orange vegetables (including yams, carrots, mangoes, cantaloupe, apricots, butternut squash, and sweet potatoes), and asparagus, spinach, kale, bok choy. If you wish for additional supplementation, the recommended dose is approximately 15,000 to 25,000 I.U. of beta-carotene daily.