In understanding what does Vitamin D do for our bodies, it is important to know that Vitamin D is a fat-soluble vitamin that works at a cellular level. It is naturally present in very few foods, added to other foods and termed 'fortified with Vitamin D', and also available as a dietary supplement. The most natural of all sources however, is when ultraviolet B (UVB) rays from the sun (or tanning beds) strike the human skin and trigger vitamin D synthesis.
Vitamin D obtained from any of the above sources is actually biologically inert and must first undergo two hydroxylations within the body before it is of any use to the body:
The following list illustrates some of the reactions within our bodies after the above hydroxylations:
To quote Dr. Greg Plotnikoff, Medical Director, Penny George Institute for Health and Healing, Abbott Northwestern Hospital in Minneapolis:
"Because vitamin D is so cheap and so clearly reduces all-cause mortality, I can say this with great certainty: Vitamin D represents the single most cost-effective medical intervention in the United States."
Research has shown the correlation between poor Vitamin D function and all sorts of health conditions, such as:
Reporting on what does Vitamin D do for cancer, the Vitamin D Research Council has compiled a long list of various cancers' success after Vitamin D treatment or programs. This includes bladder, brain, breast, Cervical, colorectal, Endometrial, Esophageal, Gallbladder, Gastric, Hodgkin, Leukemia, Lung, Melanoma, Multiple Myeloma, non-melanoma skin cancer, non-hodgekin lymphoma, ovarian, Pancreatic, Prostate, and Renal.
Some interesting facts include:
Cardiovascular disease (CVD) is also referred to as heart and circulatory disease, includes conditions such as coronary heart disease (angina and heart attack). Dr. JoAnn Manson, Professor, Department of Epidemiology at Harvard School of Public Health, Professor of Medicine at Harvard Medical School, and Chief of Division of Preventive Medicine, Department of Medicine, at Brigham and Women's Hospital, when asked what does Vitamin do for the heart, was quoted as saying...
"I think vitamin D is one of the most promising nutrients for prevention of cardiac disease and cancer, and I believe in it strongly."
Autoimmune diseases arise when the body actually attacks its own cells as it mistakes some part of the body as a pathogen and attacks it. So what does Vitamin D do to benefit patients with an autoimmune disease such as HIV or AIDS?
More than 40 million adults in the United States alone have or are at risk of developing osteoporosis, which is a disease characterized by low bone mass and structural deterioration of bone tissue that increases the fragility of bones and significantly increases the risk of bone fractures. Osteoporosis is most often associated with inadequate calcium intakes, but insufficient vitamin D contributes to osteoporosis by reducing calcium absorption.
Osteoporosis is an example of a long-term effect of calcium and vitamin D insufficiency in the body, whereas rickets and osteomalacia are extreme examples of vitamin D deficiency. What does Vitamin D do when adequately stored in the body and thereby maintaining good bone strength? It helps prevent:
Normal bone is constantly being remodeled. During menopause, the balance between these processes changes, resulting in more bone being resorbed than rebuilt. Hormone therapy with progesterone also might be able to delay the onset of osteoporosis. Among postmenopausal women and older men, supplements of both vitamin D and calcium result in small increases in bone mineral density throughout the skeleton. They also help to reduce fractures in institutionalized older populations.
What does Vitamin D do to help prevent depression?
"Doses" of sunlight or simulated sunlight timed carefully upon arrival in a new time zone, can re-set your body's biological clock resulting in less day time drowsiness and better quality night time sleep.
Institute of Medicine, Food and Nutrition Board. Dietary Reference Intakes for Calcium and Vitamin D. Washington, DC: National Academy Press, 2010.
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