Vitamin C

Vitamin C is important to all animals, including humans, because it is vital to the production of collagen. Vitamin C is also important because it helps protect the fat-soluble vitamins A and E as well as fatty acids from oxidation. Vitamin C prevents and cures the disease scurvy, and can be beneficial in the treatment of iron deficiency anemia.

Most animals manufacture their own vitamin C, but man, primates (apes, chimps, etc.) and guinea pigs have lost this ability.

Famous in the history of the sea is the disease called scurvy which occurred when the seamen had no vitamin C in their diet. Scurvy symptoms include bleeding and inflamed gums, loose teeth, poor wound healing, purplish spots called petechiae on the skin, easy bruising, bumps of coiled hair on the arms and legs, pain in the joints, muscle wasting and general deterioration. It was found that the inclusion of citrus fruits in the diets of the sailors prevented the disease by supplying vitamin C. Scottish physician James Lind is credited with advising the British Navy in 1753 to carry fresh vegetables and fruits onboard to prevent scurvy. Acting on his advice some forty years later the British Navy carried lime juice on long sea journeys, earning the nickname "limeys" for the British sailors. Since vitamin C is readily available in the diet, scurvy is now rare except in alcoholics who receive their entire calorie intake from alcohol.

Vitamin C is found in cirtrus fruits such as oranges, limes, and grapefruit, and vegetables including tomatoes, green peppers, potatoes and many others. Vitamin C is easily damaged during food preparation stages such as chopping, exposure to air, cooking and being submerged in water. The amount of vitamin C in common foods is high enough that the quantity which remains after processing is usually more than enough for a daily supply.

The recommended daily allowance (RDA) of vitamin C is 60-90 milligrams. Smokers are advised to take 35 mg more since smoking depletes vitamin C. Alan and Clemetson report an average of 72 mg/day for U. S. citizens.

Collagen

Collagen is abundant and vital in the human body because it is the most abundant of the fibers in connective tissue. Connective tissue gives our body form and supports our organs. Indicative of the importance of collagen is a list of five types of collagen and their locations in the body.

The manufacture of collagen in the body involves a sequence of events both inside and outside of a forming cell. Vitamin C is active inside the cell, where it hydroxylates (adds hydrogen and oxygen) to two amino acids: proline and lysine. This helps form a forerunner molecule called procollagen that is later packaged and modified into collagen outside of the cell. Without vitamin C, collagen formation is disrupted, causing a wide variety of problems throughout the body.