Vitamin C
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VITAMIN C
Vitamin C, also known as ascorbic acid, is a water-soluble vitamin. Unlike most mammals, humans do not have the ability to make their own vitamin C. Therefore, we must obtain vitamin C through our diet.
FUNCTION
Vitamin C is required for the synthesis of collagen, an important structural component of blood vessels, tendons, ligaments, and bone. Vitamin C also plays an important role in the synthesis of the neurotransmitter, norepinephrine. Neurotransmitters are critical to brain function and are known to affect mood. In addition, vitamin C is required for the synthesis of carnitine, a small molecule that is essential for the transport of fat to cellular organelles called mitochondria, for conversion to energy (1). Recent research also suggests that vitamin C is involved in the metabolism of cholesterol to bile acids, which may have implications for blood cholesterol levels and the incidence of gallstones (2).
Vitamin C is also a highly effective antioxidant. Even in small amounts vitamin C can protect indispensable molecules in the body, such as proteins, lipids (fats), carbohydrates, and nucleic acids (DNA and RNA) from damage by free radicals and reactive oxygen species that can be generated during normal metabolism as well as through exposure to toxins and pollutants (e.g. smoking). Vitamin C may also be able to regenerate other antioxidants such as vitamin E (1).
DEFICIENCY
Scurvy
Severe vitamin C deficiency has been known for many centuries as the potentially fatal disease, scurvy. By the late 1700s the British navy was aware that scurvy could be cured by eating oranges or lemons, even though vitamin C would not be isolated until the early 1930s. Symptoms of scurvy include bleeding and bruising easily, hair and tooth loss, joint pain and swelling. Such symptoms appear to be related to the weakening of blood vessels, connective tissue, and bone, which contain collagen. Early symptoms of scurvy such as fatigue may result from diminished levels of carnitine, needed to derive energy from fat, or decreased synthesis of the neurotransmitter norepinephrine (see Function). Scurvy is rare in developed countries because it can be prevented by as little as 10 mg of vitamin C daily (2). However, recent cases have occurred in children and the elderly on very restricted diets (4,5).
Ascorbic Acid / Vitamin C is an essential nutrient that Humans, as well as Apes and Guinea pigs
must obtain from dietary sources. Most other animals produce ascorbic acid in the liver from glucose,
and in much higher amounts than we get from our diets today.
Vitamin C is found mostly in fruits and vegetables, where the highest concentrations are in fresh, rawfoods, while whole grains, seeds, or beans contain very little Vitamin C, except when they are sprouted,
which raises the ascorbic acid content. Similarly, animal foods contain almost no Vitamin C, although
raw fish has enough to prevent deficiency symptoms. Vitamin C is water-soluble and one of the leaststable vitamins. Cooking can destroy much of the Vitamin C content in food, and it is easily oxidized inair and sensitive to light. Being mostly contained in the watery part of fruits and vegetables, Vitamin Cis easily lost during cooking in water, so the steaming of vegetables minimizes its loss.
Ascorbic acid was isolated from lemons in 1932, following the discovery of its link to scurvy. It was first
written about circa 1500 B.C. and described by Aristotle in 450 B.C. as a syndrome characterized by
lack of energy, tooth decay, gum inflammation, and bleeding problems. A high percentages of sailors
with the British navy and other fleets used to die from scurvy until James Lind discovered that the juice
of lemons could cure and also prevent the disease. The ships then routinely carried limes for the sailors
to consume daily, and thus these sailors became known as “limeys.” Only about 10mg of Vitamin C is
necessary to prevent scurvy.
Ascorbic acid is used up more rapidly with alcohol use, smoking, and under stressful conditions. Otherfactors that increase Vitamin C requirements include viral illness and fever, ASA and other medications
(sulfa antibiotics, cortisone), environmental toxins (DDT), and exposure to heavy metals such as lead,mercury, or cadmium. Vitamin C is involved in the formation and maintenance of collagen, which is the
basis of connective tissue found in capillary walls, skin, ligaments, cartilage, vertebral discs, joint linings,
bones and teeth. Collagen, and thus Vitamin C, is needed for wound healing and to maintain healthy
blood vessels.
Vitamin C helps thyroid hormone production and the metabolism of folic acid, tyrosine, and tryptophan,and it stimulates adrenal function and the release of norepinephrine and epinephrine, which are stresshormones. However, prolonged stress depletes Vitamin C in the adrenals and decreases blood levels.
Ascorbic acid is further important in cellular immune functions, where it may be helpful against bacterial,viral, and fungal diseases. At higher amounts, Vitamin C may decrease the production of histamine,
thereby reducing allergy potential.
A combination of very high doses of Vitamin C + Vit E + Vit B12 has been found effective in lesseningthe symptoms of shingles (herpes zoster), provided they are all taken at the earliest onset of the attack.
Vitamin C helps the absorption of iron (particularly the vegetable, or non-heme form), so it is helpful for
iron-deficiency anemia. Other conditions that benefit from ascorbic acid metabolism include diabetes
(for insulin production), certain cases of male infertility, as well as arteriosclerosis, atherosclerosis,
cataracts, glaucoma and musculoskeletal degeneration (mostly by Vitamin C keeping calcium soluble
and preventing it from going to high).
When no other test methods are available, most doctors recommend the “Bowel Tolerance Challenge”