Vitamin D-3 (Cholecalciferol)

Cholecalciferol, or Vitamin D3 is a fat soluble, steroidal hormone, that is sometimes  mis-represented as a ‘vitamin, or enzyme co-factor.’  The precursors to Vitamin that is found in food, and production of Vitamin D3 from these precursors requires exposure to UV light, found in abundant sunshine.

Vitamin D exists in several inactive precursor forms, each with a different level of activity. The liver and kidney are involved in the production of active  vitamin D.

The major biologic function of vitamin D is to maintain normal blood levels of calcium and phosphorus. Essential to calcium absorption, vitamin D helps to form and maintain strong bones, but the many other actions of Vitamin D are far more interesting.  Acting on the cell nucleus,  Vitamin D is involved in genetic expression, and it is in this role that it is important in the immune system and in the prevention of cancer.

Current research indicates vitamin D deficiency is involved  in prevention of seventeen varieties of cancer as well as heart disease, stroke, hypertension, autoimmune diseases, diabetes, depression, chronic pain, osteoarthritis, osteoporosis, muscle weakness, muscle wasting, birth defects, and periodontal disease.

What is important to note about Cholecalciferol is that deficiencies haves been found to cause colon, breast and prostate cancer, a variety of auto-immune diseases(1), and the doses necessary to prevent these disorders is approximately 5 times the minimum daily requirement or “RDA.”

The reduction in the incidence of breast cancer, alone, is estimated to be 50%.(2) Recommended intake of Vitamin D3 is thought to be  2000 IU/day, or more.  Thought to decrease the risk of type 1 diabetes, cardiovascular heart disease and autoimmune diseases, the ‘safe or desired’ blood level of Vitamin D is being reconsidered. (3) Direct association between the incidence of MS has been seen in a homogenous population in Australia (4), and serum Vitamin D levels were found to be a risk factor in the development of multiple sclerosis.(5)

Vitamin D is a selective regulator of the immune system, and therapeutic use has been demonstrated to inhibit the development of autoimmune diseases, (6) and Vitamin D has been shown to decrease the risk of developing MS by 40%(7)

As educated and reasonable practitioners, we should be fast to recognizing the risk-reward ratio of the use of Vitamin D, in this way.

Information is becoming increasingly available on the importance of cholecalciferol.  In recommending this to your patients, it is of vital importance that they use the proper form, which is labeled “Vitamin D-3.”

NOTE:  Vitamin D is lipid soluble and should be taken with oil.  Fish oil capsules work well.  The recommended daily dosage is 2000 IU per day, and it can be expected to cause some dyspepsia, initially.

Vitamin D-3 5000 IU
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  1. Peterlik M & Cross HS: Dysfunction of the vitamin D endocrine system as common cause for multiple malignant and other chronic diseases. Anticancer Res: 26(4A: 2581-9, 2006.
  2. Garland CF, Gorham ED, Morhr SB et al:       Vitamin D and prevention of breast cancer: Pooled analysis. J Steroid Biochem Mol Biol 103:(3-5):703-11, 2007.
  3. Holick MF: Vitamin D: important for prevention of osteoporosis, cardiovascular heart disease, type 1 diabetes, autoimmune diseases, and some cancers. South Med J 10:1024-7, 2005.
  4. Tajouri L, Ovcaric M, Curtain R, et al:       Variation in the vitamin D receptor gene is associated with multiple sclerosis in an Australian population. J Neurogenet 19:25-38, 2005.
  5. Munger KL, Levin LI, Hollis BW et al:       Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis. JAMA 23:2832-8, 2006.
  6. Cantorna MT, and Mahan BD: D-hormone and the immune system. J Rheumatol Suppl 76:22-10, 2005.
  7. Brown SJ: The role of vitamin D in multiple sclerosis. Ann Pharmacother 6:1158-61, 2006.
About David S Klein, MD 149 Articles
David S. Klein, MD, FACA, FACPM was born in Washington, DC, and was raised in Chevy Chase, Maryland. He completed his undergraduate education at the University of Maryland with degrees in Chemistry and Psychology. Medical School was completed at the University of Maryland at Baltimore, followed by Internship in General Surgery at the University of North Carolina and Residency in Anesthesiology at the Duke University, Durham, North Carolina. Dr Klein has been practicing medicine since 1983, concentrating in Pain Medicine, Minimally Invasive Medicine and Surgery, and Neuroendocrinology. Earning Board Certification in Anesthesiology, Dr. Klein was elected Fellow in the American College of Anesthesiology, and he was elected Fellow in the American College of Pain Medicine. He is currently an adjunct Associate Professor at the University of Central Florida, School of Medicine. He has focused his private practice on treating patients with hormone imbalance issues, nutritional deficiency related medical problems as well as pain related issues and impairment. With a highly-complex, CLIA licensed laboratory in-house, he has been able to provide rapid-turn around analysis efficiently and cost-effectively. Lecturing extensively nationally as well as internationally, Dr. Klein has authored many articles on topics relating to pain, injury and nutritionally modulated illness. His radio show, “Pain Free Living,” received top ratings during the 6 years it was on the air. Currently practicing in Longwood, Florida, Dr. Klein practices entirely in the office setting.