Citrus fruit is a source of vitamin C are useful for human health. Vitamin C is very diverse antarvarietas, but ranged between 27-49 mg/100 g of fruit flesh. Orange juice contains 40-70 mg of vitamin C per 100 ml, depending on its type. The more old citrus fruit, usually diminishing its vitamin C content, but the more sweet taste.

Vitamin C found in fruit juice, meat, and leather. A quarter part of the total content of vitamin C contained in citrus fruit juice. Beta-carotene (provitamin A), which forms vitamin A contained in many skin and orange juice. Vitamin C plays a role in the process of absorption of inorganic iron (iron and food) which can prevent and help cure anemia (blood drawn).

Vitamin C also has the ability as an antioxidant, which can help prevent cell damage from free radical molecules activity. In the body, free radicals oxidize molecules of protein, fatty acids, and DNA. Free radical damage has implications for the emergence of a number of diseases, including cancer, cardiovascular disease, and cataracts.

Significantly, new research shows that a high intake of vitamin C from foods, including oranges, can prevent the increase of oxidized LDL. High oxidized LDL is the main factor of developing heart disease. Several epidemiological studies have indeed shown a significant relationship between intakes of vitamin C with the risk of death from cardiovascular disease.

Vitamin C in fruits, including oranges, it has been scientifically proven to protect the body against cancer. The results of epidemiological studies indicate that consumption of fruit (one of them orange) and vegetables that are high, have a protective effect against cancers better compared with the consumption of vitamin C in the form of tablets or other supplements.