Ascorbic acid, otherwise known as vitamin C is a vitamin that is water soluble and found in a number of foods ranging from fruits to vegetables. It is known for its antioxidant capability protecting you from free radical damage. Vitamin C is also important for the production of collagen which is a protein found in connective tissues. Connective tissue acts as a glue material that holds your entire body together. It is found between cells, tissues and organs essentially keeping you from falling apart. Vitamin C is also important to the immune system by helping you to heal when you cut or bruise yourself. It is also important for the absorption of iron from the diet. A vitamin C deficiency is characterized by black inflamed gums which generates scurvy that was common so long ago. Vitamin C is also important for vascular health maintaining the endothelial cell membranes helping to reduce arteriosclerosis. This vitamin is listed as essential as we don't have a gene that codes for it. Interestingly, most other plants and animals have the ability to make this vitamin.
Vitamin C is important during oxidative stress. Highly reactive oxygen species can generate an imbalance that can interact with structural components of your cells as well as damage or block certain metabolic pathways. Damaged structural components and blocked pathways can initiate a number diseases such as cardiovascular incidents, cancer, DNA damage, nervous system problems and contribute to the aging process. Although we have genes that code for superoxide dismutase, catalase and various peroxidases, they are not always sufficient to get the job done. As we age mutations accumulate in these genes and with time the production of these enzymes decreases. Acquiring antioxidants whether from our diets and/or supplementation becomes crucial as we age. In other words, the antioxidant enzymes we code for are nicely complemented with the antioxidants we take in our diets. This is particularly the case with Vitamin C, Vitamin E (lipid soluble) and glutathione. Depending on the antioxidant, they may be soluble in water, lipids or both. This determines where their sites of action will occur.
Antioxidants go beyond being free radical scavengers but are also involved in the regulation of gene expression, may act as coenzymes, signal transduction as well as programmed cell death or what is known as apoptosis. All organisms contain suicide genes that can be activated when a cell runs awry. Killing a cell that has run amok keeps it from reproducing itself and spreading into surrounding tissue. This is important for maintaining homeostasis within the body. Homeostasis simply means maintaining a balance or minimal range of molecular activity to prevent wild swings in pathways which can be devastating to overall function bringing about disease states.
Dietary sources of vitamin C come as Ascorbic acid and DHAA (dehydroascorbic acid). DHAA is just the oxidized form of vitamin C. These 2 forms are easily absorbed in the gut as well as in the kidney. Once ingested, vitamin C flows around in blood and can enter all cells of the body. Vitamin C has a number of ways it can get inside a cell. Simple passive diffusion is not one of them. As vitamin C is water soluble it would have difficulty getting through the membrane lipids. In passive diffusion, atoms and/or molecules are able to bounce right through a plasma membrane. Vitamin C can't quite do that so it requires specific transport systems. In some cases DHAA (the oxidized form of vitamin C) is transported by facilitated diffusion through a glucose-sensitive or insensitive transporter. Facilitated transport refers to a molecule being helped across the plasma membrane but doesn't require the use of energy in the form of ATP to do it. Other forms of vitamin C transport include the release of vitamin C from secretory vesicles and active transport. Active transport requires the use of energy to drive it and in this case vitamin C passes through a sodium-dependent vitamin C transporter channel. Recent research indicates that these transport systems operate differently under different physiological states and their function may be changed with disease states as well as aging.
Why You Should Take Vitamin C
The benefits of vitamin C have been known for a long time and it is known to be one of the safest and most effective vitamins. Keep in mind it is important to a wide range of tissues including the immune system, cardiovascular system, skin and eyes to mention a few. High levels of vitamin C in your bloodstream just may be a marker of good health.
Are you getting enough vitamin C? Are you able to feel all the benefits of vitamin C? Some healthcare providers believe that the RDA is insufficient and in fact you might want to consider taking 5 times that amount. Although vitamin C is readily available in many fruits and vegetables we eat, it may be difficult to eat all the servings you need. Supplementation may be required to experience all the benefits of vitamin C. It is suggested that you take somewhere between 500 to 2,000mg a day depending on the form you take. Timed released forms are an excellent choice because they will maintain a constant level of vitamin C throughout the day affording continual protection.