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
Scurvy like Gilbert Blane and Thomas Trotter and by the reports of up-and-coming naval commanders. With the coming of war in 1793, the need to eliminate scurvy acquired a new urgency. But the first initiative came not from the medical establishment but from the admirals. Ordered to lead an expedition against Mauritius, Rear Admiral Gardner was uninterested in the wort, malt and elixir of vitriol which were still being issued to ships of the Royal Navy, and demanded that he be supplied with lemons, to counteract scurvy on the voyage. Members of the Sick and Hurt Board, recently augmented by two