Though many animals can synthesize it in their body and are free from scurvy, unfortunately man has to depend on his food sources for vitamin C. Inadequate or irregular intake of ascorbic acid can lead to clinical manifestations of this disease in two to three months.
The vitamin C availability in vegetables decreases inversely in proportion with the length of storage and the temperature at which stored. Longer cooking duration and boiling for longer time causes reduction in the availability of vitamin C.
Subclinical form of vitamin C deficiency exists in many people leading to diseases like cardiac disease, strokes, diabetes etc. Clinical prevention of scurvy disease can be achieved with daily intake of about 100 gm of vitamin C.
Vitamin C is abundantly available in the citrus fruits. However the richest sources of ascorbic acid are not citrus fruits. Ten known richest sources are described here under in the order of richness in ascorbic acid.
During the biological process of metabolism and energy production a number of free radicals (reactive oxygen species) are generated in the body which are useful, in small quantities, for further biological activities.
Excess ascorbic acid may interfere with the pro oxidant-antioxidant balance in the human body and reversely lead to decrease in immunity. In children severe skin rashes and abdominal cramps have been observed on high ascorbic acid ingestion.
A person's age, gender, health condition, food habits, surroundings and many other factors decide whether the given quantity is excess overdose for him. To determine a quantity as excess of vitamin C is a controversial matter.
The scurvy treatment is simple and easy and in about a month of treatment complete recovery can be achieved. Treatment of scurvy involves intake of vitamin C rich citrus fruits, vegetables and vitamin C supplements.
Dietary deficiency of ascorbic acid may be due taking diet poor in this vitamin. Diet lacking fresh fruits and vegetables leads to the ailment. Infantile scurvy is sometimes found in babies, whose mothers had taken very high doses of ascorbic acid during pregnancy.