Vitamin C is a water-soluble nutrient essential for life, used by the human body for many purposes.
Vitamin C deficiency
Lack of ascorbic acid in the daily diet leads to a disease called scurvy, a form of avitaminosis that is characterized by:
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loose teeth
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superficial bleeding
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fragility of blood vessels
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poor healing
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compromised immunity
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mild anaemia.
Daily requirement
There is a continuing debate within the scientific community over the optimum amount of vitamin C for humans.
Vitamin C is needed in the diet to prevent scurvy. It also has a reputation for being useful in the treatment of colds and flu. The evidence to support this idea, however, is ambiguous, unless the studies are divided by dose size and dosing regime. When that is done, it is remarkable that most of the studies showing little or no effect employ quite small doses of ascorbate such as 100mg to 500mg per day. ("small" according to the vitamin C advocates) The Vitamin C foundation (1) recommends 8 grams of vitamin C every half hour in order to show an effect on the symptoms of a cold infection that is in progress.
High doses (thousands of mg) may result in diarrhoea, which is harmless if the dose is reduced immediately. Some researchers (Cathcart) claim the onset of diarrhoea to be an indication of where the body’s true vitamin C requirement lies. Both Cathcart and Cameron have demonstrated that very sick patients with cancer or influenza do not display any evidence of diarrhoea at all until ascorbate intake reaches levels as high as 200 grams (1/2 pound).
The small size of the ascorbic acid molecule means the kidneys cannot retain it in the body. Some other explanation is required to explain why very sick persons retain such huge quantities of vitamin C without any discharge. Quite a low level in the blood serum will cause traces to be present in the urine. All vitamin C synthesising mammals have traces in the urine at all times. The fact that animals like rats pass ascorbate into their urinary tract, after expending valuable energy manufacturing it, implies that there is a benefit to having vitamin C passing through, and this does not represent waste.
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