Vitamin C Vitamin C or ascorbic acid is probably the most popular of vitamins. It is soluble in water and is absorbed into the blood in the upper and middle part of the small intestine. Its function is to protect body tissue, regulate the metabolism of amino acids, support self-defence of the body, degrade cholesterol, stimulate the production of white blood cells and many others. By taking vitamin C as a nutritional supplement, the body receives as much than it needs and removes the remainder through urine. Therefore, it is not possible to overdose it. On the other hand, gingival bleeding, hair loss, depression, insomnia, bruising and poor performance often occur with vitamin C deficiency. It is good to supplement Vitamin C to maintain balance.