Vitamin C Background and Benefits
Vitamin C is a collective term for a group of structurally similar compounds that are based on the ascorbate anion (C6H8O6). It is an essential nutrient in humans, meaning that it is necessary for life and cannot be synthesized in the body. In addition to free ascorbate, vitamin C compounds also include ascorbic acid, dehydroascorbic acid and many of their salts and esters. Ascorbic acid and ascorbate readily interconvert in the body, depending on the pH.
Fruits and vegetables are generally abundant sources of vitamin C. The camu camu fruit and Kakadu plum have the highest concentrations of vitamin C. However, citrus fruits such as oranges are the most abundant sources of vitamin that are widely available. Organ meats such as liver also have high levels of vitamin C.
Vitamin C is a cofactor in multiple enzymatic reactions, especially those dealing with collagen synthesis. It also has strong antioxidant properties that help to protect cells from oxidative stress, which can cause a variety of age-related conditions. All plants and animals require vitamin C, but only a few of them are unable to biosynthesize it. Humans and guinea pigs are the most notable exceptions, as are most bats and some other primates.
L-ascorbic acid is the most common form of vitamin C used in health supplement, primarily because of its low production cost. However, more expensive forms such as ascorbyl palmitate and calcium ascorbate have greater antioxidant activity.
Ascorbyl palmitate (C22H38O7) is an ester of ascorbic acid and palmitic acid that is commonly known as vitamin C ester. It is primarily used to add vitamin C to both health supplements and food additives. Ascorbyl palmitate breaks down into its individual components during digestion, allowing the ascorbic acid to be absorbed into the bloodstream. Palmitic acid is a saturated fatty acid, which makes ascorbyl palmitate fat soluble. This property allows palmitic acid to penetrate cell membranes, enhancing ascorbyl palmitate’s antioxidant effect.
Calcium ascorbate is the calcium salt of ascorbic acid and has the chemical formula CaC12H14O12. It is a natural form of vitamin C and is also a source of calcium, since calcium comprises about 10 percent of its mass. Calcium ascorbate breaks down easily in the stomach and the HCL converts the ascorbate ion to ascorbic acid. This process allows vitamin C to be quickly absorbed into the bloodstream without increasing the acidity in the stomach.
Uses of Vitamin C
The benefits of vitamin C as a health supplement generally relate to its antioxidant properties and its role in collagen synthesis. These benefits include support for the immune system, cardiovascular system, healthy blood pressure and joint function.
Immune system support
High doses of vitamin C may support the immune system by shortening the duration of systemic infections. Most studies show that this regimen may reduce the course of a cold by at least one day.
Joint health support
Calcium ascorbate supplements may help to retain healthy levels of cartilage in the joints, especially for older people.
Oral supplements of vitamin C may support cardiovascular health by helping to manage the rate at which calcium is deposited into the arterial walls. This may be a preventative as well as a therapeutic effect.Vitamin C may help to maintain healthy circulation, especially systolic pressure.
Signs You May Need Vitamin C
Signs you may need vitamin C are generally the result of unstable collagen. The first signs of a vitamin C deficiency are often brown spots on the skin that gradually increase in size. Additional signs include soft gums and spontaneous bleeding from mucous membranes. A prolonged vitamin C deficiency can cause open wounds on the skin.
Synonyms and Similar Forms of Vitamin C
Ascorbic acid, Ascorbyl palmitate
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