One of the oldest known medical texts, the Ebers Papyrus of Ancient Egypt, describes symptoms associated with eating inadequate quantities of foods that are rich in vitamin C (ascorbic acid). The condition is called scurvy, and the symptoms include swollen gums, loose teeth, black-and-blue spots or open sores on the skin, and slow wound healing. The disease was especially prevalent in seamen on long sea voyages during the sixteenth and seventeenth centuries who primarily ate nonperishable foods that lacked this essential vitamin. Relief from scurvy finally came about when the curative properties of ascorbic acid-containing citruses were discovered in 1747 by the Scottish naval surgeon, James Lind. Naturally abundant in many fruits and vegetables, vitamin C is especially rich in citrus fruits such as oranges, lemons, tangerines, and limes. Although treatment with ascorbic acid usually achieves a quick recovery from the effects of scurvy, not all damage is reversible, especially that occurring in non-regenerative tissues such as eye cornea, nerve tissue, and calcified bone. Today, advanced techniques that help preserve freshness and the availability of a large variety of vitamin C-rich foods have almost eradicated this disease.