vitamin C

vitamin C, water-soluble, carbohydrate-like substance that is essential for human health. Chemically, it is a six-carbon organic compound closely related to carbohydrates. Its ability to readily donate electrons makes it a powerful antioxidant, enabling it to protect cells from damage caused by highly reactive molecules known as free radicals.

Unlike most mammals, humans, other primates, guinea pigs, and some bats cannot synthesize vitamin C because they lack a key enzyme needed for its production. As a result, these animals must obtain the vitamin through their diet. In humans, vitamin C deficiency causes scurvy, a disease characterized by fatigue, joint pain, swollen and bleeding gums, poor wound healing, and hemorrhages. Scurvy was once common among sailors and others with limited access to fresh fruits and vegetables.

Vitamin C is essential for various biological processes. In particular, it is required for the synthesis of collagen, a structural protein that is a major component of skin, blood vessels, bones, cartilage, and other connective tissues. Consequently, the vitamin is important for growth, tissue maintenance, and wound healing. In addition to its antioxidant activity, it also helps in stimulating the immune system.

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nutritional disease: Vitamin C

Vitamin C was first isolated in 1928 by Hungarian biochemist Albert Szent-Györgyi and was identified as the factor that prevents scurvy in 1932. His work helped establish the connection between vitamins and human health and contributed to a broader understanding of nutritional deficiencies.

Relatively large amounts of vitamin C are required. Adults, for example, generally require about 75–90 milligrams of vitamin C per day, although requirements vary with age, sex, pregnancy, smoking status, and other factors. Citrus fruits and fresh vegetables are the best dietary sources of the vitamin.

Because vitamin C is easily destroyed by reactions with oxygen, especially in neutral or alkaline solution or at elevated temperatures, it is difficult to preserve in foods. The same chemical properties that make it an effective antioxidant also allow it to be used as a food additive to help prevent browning and other forms of oxidation in fruits and processed foods.