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 fat malabsorption such as pancreatitis, cystic fibrosis, tropical sprue, and biliary obstruction. Other causes of vitamin A deficiency are inadequate intake, fat malabsorption, or liver disorders. Deficiency impairs immunity and hematopoiesis and causes rashes and typical ocular effects (e.g., xerophthalmia, night blindness). Along with poor diet, a large amount of infection and disease is present in many developing communities. Infection is very draining on vitamin A reserves and this vitamin A deficit leaves the individual more susceptible to infection; increased documentation of xerophthalmia has been seen after an outbreak of measles and the varying stages of xerophthalmia become a good