Vitamin C is a water soluble vitamin present in almost all plant and animals. Humans (and other high primates), cannot produce their own body supply of vitamin C, and therefore require a dietary intake. The vitamin is required for many body functions. Here is a list of some bodily processes where vitamin C is involved:
- Formation of collagen - the body's intracellular "cement"
- Growth, tissue repair and healing
- Formation of antibodies and stimulation of the white blood cells
- Formation of corticosteroid hormones in the adrenal gland
- Absorption of ..and its necessary accumulation in the bone marrow, spleen and liver.
- As an antioxidant nutrient, it protects water-soluble substances from oxidation by allowing itself to be oxidised.
- As an anti-histamine, vitamin C reduces the effect of histamine produced by the immune system. Histamine is responsible for many of the symptoms of allergies such hay fever.
- Carnitine formation in vegetarians, together with lysine.
Lack of vitamin C in a regular diet can cause a deficiency disease known as scurvy. The symptoms include bleeding of the gums and loosening of the teeth, together with lassitude, weakness, irritability and muscle ache. The recommended daily allowance of vitamin C is set at 60mg.
Studies have shown that vitamin C levels become depleted during infection. An increase to 1 gram a day has been shown to help symptoms of the common cold. Asthmatics have reduced levels of vitamin C in their blood (1). Use of vitamin C supplements have been shown to reduce the severity of asthma attacks(2) and protect against exercise induced asthma(3).
Sources of Vitamin C
The main sources of vitamin C in the diet are potatoes, fruit juices, citrus fruit and green vegetables. The vitamin C content of foods varies very widely depending upon season, variety and freshness.
Foods and vitamin C content:
1. "Healing Through Nutrition",
Dr M Werbach, Thorsons, 1993.
2. Anah CO, Jarike LN and Baig HA> High dose ascorbic acid in Nigerian Asthmatics. Trop Geograph Med, 32:132-137, 1980.
3. Schachter EN and Schlesinger A. The attenuation of exercise-induced bronchospasm by ascorbic acid.. Ann Allergy, 49:146-150, 1982.