You need several nutrients to support your vision, immune function, and your overall health; but did you know there is one essential nutrient so important to your health that it was given the name "the anti-infective vitamin" in the year 1928? In this episode, we shine the spotlight on a nutrient that can be overlooked in many Western countries but is no less critical for human development and daily function - Vitamin A. First, we will look at the different forms of vitamin A as part of the "retinoid" family - differentiating between preformed vitamin A (active and stored) and provitamin A compounds, their roles in promoting human health and the consequences of vitamin A deficiency in the following bodily functions:Vision function - vitamin A's role in image and non-image vision.Red blood cell formation - Vitamin A's impact on iron-deficiency anemia.Immune function - Vitamin A's importance in maintaining physical barriers against infection.Fetal development - How some forms of vitamin A act to stimulate gene expressionWe will look to understand the prevalence of vitamin A deficiency in lower and middle-income countries, as well as the United States, and the impact deficiency has on women and children (i.e., groups at the highest risk of deficiency worldwide).Next, we will examine vitamin A requirements and sources (from plant and animal foods). We will gather an understanding of how provitamin A from food and supplements contribute differently to vitamin A status, how not all provitamin A compounds were created equal, and how/why some food sources might be better than others for extracting provitamin A to be converted into active vitamin A in the body. We conclude this episode by exploring the toxicity of retinoid compounds and how specific studies suggest that high doses of preformed vitamin A may increase the risk of certain cancers in the body (we will also attempt to understand why that is). Be sure to subscribe for future episodes covering specific nutrients and strategies for achieving optimal nutrient adequacy.Support the show