Vitamin A is commonly known as the anti-infective vitamin, because it is required for normal functioning of the immune system . The skin and mucosal cells (cells that line the airways, digestive tract, and urinary tract) function as a barrier and form the body’s first line of defense against infection.Both vitamin A excess and deficiency are known to cause birth defects.Red blood cells, like all blood cells, are derived from precursor cells called stem cells. These stem cells are dependent on retinoids for normal differentiation into red blood cells. Additionally, vitamin A appears to facilitate the mobilization of iron. (more…)