Complex metabolic processes in our body are constantly working together to achieve what is known as homeostasis, or balance. This balance can be disrupted easily if any part of the complex or system is deficient or malfunctions. Vitamins are critical components of these processes at various levels, such as: growth, development, repair, metabolic, and disease prevention just to name a few.
A shortage or deficiency of vitamins, which we cannot produce on our own and have to ingest, results in a disruption of our delicate life processes with potentially devastating consequences. The following examples illustrate this point.
Vitamin A is important for vision and it is the anti-infective vitamin, because it is required for normal functioning of the immune system. Its deficiency causes birth defects, night blindness, and an increased proneness to infectious diseases.
Zinc deficiency results in decreased activity of the enzyme that releases retinol from its storage form, retinyl palmitate, in the liver, thus depreciating the effects of Vitamin A. To make things worse, Vitamin A deficiency may exacerbate iron deficiency anemia. Vitamin A supplementation has beneficial effects on iron deficiency anemia and improves iron nutritional status among children and pregnant women.
We must ingest Vitamin B 6 because the human body cannot synthesize it. Vitamin B 6 and the coenzyme, PLP plays a vital role in the function of approximately 100 enzymes that catalyze (allow) essential chemical reactions in the human body. For example, PLP functions as a coenzyme for glycogen phosphorylase, an enzyme that catalyzes the release of glucose stored in the muscle as glycogen. Releasing glucose is vitally important, as the brain requires a constant supply of glucose to function.
Vitamin B 12 is the largest and most complex of all the vitamins. It is unique among vitamins in that it contains a metal ion, cobalt. For this reason, cobalamin is the term used to refer to compounds having B 12 activity. Methylcobalamin and 5-deoxyadenosyl cobalamin are the forms of vitamin B 12 used in the human body. The form of cobalamin used in most supplements, cyanocobalamin, is readily converted to 5-deoxyadenosyl and methylcobalamin.
Methylcobalamin is required for the function of the folate-dependent enzyme, methionine synthase. Inadequate function of methionine synthase can lead to an accumulation of homocysteine, which has been associated with increased risk of cardiovascular diseases.
Even moderately elevated levels of homocysteine in the blood have been associated with increased risk for cardiovascular diseases, such as heart disease and stroke. When we digest protein, we release amino acids, including methionine. Homocysteine is an intermediate in the metabolism of methionine. Healthy individuals utilize two different pathways to metabolize (reduce) homocysteine.
The amount of homocysteine in the blood is regulated by at least three vitamins: folic acid, vitamin B 12 , and vitamin B 6 and it is important to have adequate levels of these three vitamins to fight off heart disease and stroke.
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 can strongly influence 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, the body’s power-house for conversion to energy.
Several studies have suggested that high Vitamin C supplementation is cardio-protective (it protects the heart). Vitamin C also has strong antioxidant effects that are probably responsible for beneficial effects on Type 2 Diabetes and for its role in cancer prevention, as well as Alzheimer’s in combination with vitamin E.
Although best known for its effects on bone health, vitamin D is involved in numerous metabolic and endocrine processes in our body including modulating kidney, intestinal, and parathyroid functioning.
Vitamin E is another major antioxidant. What most people do not know is that the term vitamin E actually describes a family of eight antioxidants, four tocopherols, alpha-, beta-, gamma- and delta-, and four tocotrienols (also alpha-, beta-, gamma- and delta-). Alpha-tocopherol is the only form of vitamin E actively maintained in the human body and is therefore, the form of vitamin E found in the largest quantities in the blood and tissue. It protects us against heart disease, cancers, and buoys our immune system.
Vitamin K is an essential nutrient often associated with the clotting cascade and has been the focus of considerable research demonstrating some anticancer potential.
The interactions between free radicals and antioxidants in our body exemplify the role of vitamins and cancer. Free radicals, molecules that can attack cells, are responsible for aging, and substances found in our bodies and in food called antioxidants might just slow the damage, theorized University of California at Berkeley researcher Harman, slightly over a half century ago. Antioxidants such as vitamins C and E, selenium, beta carotene, and coenzyme Q10 (CoQ10) can reduce your risk of heart disease, cancer, and Alzheimer’s, and they might even increase your life span.
Deficiency of any of the vitamins will not only deprive you of their benefits but it will vastly increase your chances of getting a rather large variety of different diseases and disorders. Fortunately, a daily multivitamin is extremely affordable and can be bought almost anywhere. Just look for a name brand and stick with it daily.
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