Food vitamins and minerals can lead to diseases that can have far-reaching effects on health. For instance, 30% of the world's population either has, or is at risk for developing, iodine deficiency. It is estimated that at least 3 million children are blind due to vitamin A deficiency. Vitamin C deficiency results in scurvy. Calcium, Vitamin D, and phosphorus are inter-related; the consumption of each may affect the absorption of the others. Kwashiorkor and marasmus are childhood disorders caused by lack of dietary protein. Many individuals limit what foods they eat for reasons of morality, or other habit. For instance, vegetarians
Vitamin A deficiency and lymphocytes. Suppression of these result in a lack of immune reaction if pathogens become present in the body and consequently a greater susceptibility to incubation of disease. VAD and infections aggravate each other, so with infection, vitamin A levels are depleted, which in turn reduces intestinal absorption of vitamin A. Very often seen with VAD is protein energy malnutrition, in which the synthesis of retinol binding protein (RBP) is decreased, consequently the uptake of retinol is reduced. This leads to an inability to use any vitamin A present as the RBP is absent, so the retinol cannot be transported