WHY SHOULD VITAMIN D DEFICIENCY BE OF CONCERN?
Vitamin D deficiency is a condition that is becoming more widespread throughout the world. Vitamin D deficiency Syndrome (VDDS) is defined as a level below 20 ng/mL and may cause Ricket’s in children (soft bones and skeletal deformities), osteomalacia in adults (weak bones and muscle weakeness), and osteoporosis (brittle bones that may lead to fractures) in postmenopausal women and the elderly. Recent studies even show that the lack of adequate sun exposure in certain parts of the world may lead to ovarian cancer. The lack of sun exposure, the lack of a proper vitamin D-providing diet, inadequate absorption from the intestine, and inadequate conversion of vitamin D by the kidney to its active form, lead to vitamin D deficiency.

WHAT IS VITAMIN D?
Vitamin D is a fat soluble vitamin formed from a reaction between the sun’s UVB rays and a cholesterol-like steroid in the skin called 7-dehydrocholesterol. Vitamin D is also a prohormone, which means it is converted to a hormone as it is broken down by the body. It is normally obtained from two sources: sunlight (UVB rays) and in the diet. Vitamin D is key in regulating levels of calcium and phosphorus in the body by helping with their absorption from the GI tract. Vitamin D helps form strong and healthy bones. Vitamin D can also control how much parathyroid hormone is released in the body.

ADDITIONAL SOURCES OF VITAMIN D
In addition to the sun’s UVB rays, other natural sources of vitamin D include:

• Cod liver oil (1-3 tablespoons daily)
• Fatty fish: salmon, mackerel, sardines, tuna, eel
• Eggs
• Shiitake mushrooms
• Oysters
• Liver

Vitamin D can be produced in the skin with ONLY 10-15 minutes of exposure per day. Try to apply sunscreen (minimum of SPF 15) AFTER at least 15 minutes of sun exposure to protect the skin and prevent burning.

FORM OF VITAMIN D THAT SHOULD BE TAKEN
Vitamin D supplementation should be taken in the form of D3 (cholecalciferol) NOT D2 (ergocalciferol). Check your bottle of vitamins! Also, try to take a form of vitamin D supplementation that does NOT also include vitamin A (retinol) to prevent vitamin A related toxicity.

HOW MUCH VITAMIN D SHOULD BE TAKEN?
1000 IU per day for infants
2000 IU per day for children
4000 IU per day for adults
(TOTAL, INCLUDING ALL SOURCES)

• Take daily for at least 5-9 months for maximum benefit
• Obtained primarily in the form of diet and sun exposure and
• Secondarily in the form of vitamins, etc. (see additional sources above)

The requirement for how much should be taken increases with age, because the ability of the skin to produce vitamin D decreases over time. Other factors that affect how much vitamin D should be taken depends on the following:

• Season
• Geographic latitude (how far north you live)
• Time of day
• Environment
• Weight
• Skin type (darker pigmented skin produces less vitamin D)

CHECKING YOUR VITAMIN D LEVEL
You can have your vitamin D level checked by your doctor. Ask for a 25(OH)D level (which is called a calcidiol level). A 1,25(OH)D (calcitriol) level is NOT sufficient. Also have your calcium level checked periodically. An ideal level of vitamin D in your blood can range between 40-65 ng/mL.

PLEASE NOTE that it is possible to take too much vitamin D (blood levels greater than 80 ng/mL). Vitamin D toxicity usually causes nausea, vomiting, poor appetite, constipation, weakness, and weight loss. Extra vitamin D can also lead to high calcium levels in the body, causing confusion, abnormal heart rhythms, or calcium deposits in soft tissue. One may even have normal calcium levels but a hypersensitivity to vitamin D in which case vitamin D supplementation should be stopped. Please see your healthcare professional for additional information.

OTHER CLAIMED THERAPEUTIC BENEFITS
* Cardiovascular Disease * Hypertension *
*Type 1 & 2 diabetes * Osteoarthritis * Multiple Sclerosis *
* Depression * Epilepsy * *Migraines *
*Polycystic Ovary Syndrome * Musculoskeletal Pain * Cancer *

Author: Amy Shah, PharmD Candidate 2007, University of Illinois at Chicago College of Pharmacy. amyshah2181@aol.com.

References:
"Vitamin D - Wikipedia, the Free Encyclopedia." Wikipedia. 23 Jan. 2006. Wikipedia Foundation, Inc. 23 Jan. 2007 <http://en.wikipedia.org/wiki/Vitamin_D>.
"Medical Encylopedia: Vitamin D." Medline Plus. 27 Oct. 2004. U.S. National Library of Medicine, National Institiutes of Health. 23 Jan. 2007 <http://www.nlm.nih.gov/medlineplus/ency/article/002405.htm>.
Cannell, John. "Vitamin D Research." VitaminDCouncil.Com. 27 Dec. 2003. Vitamin D Council. 23 Jan. 2007 <VitaminDCouncil.com>.
Vasquez, Alex, Gilbert Manso, and John Cannell. "The Clinical Importance of Vitamin D (Cholecalciferol): a Paradigm Shift with Implications for All Healthcare Providers."
Alternative Therapies 10 (2004): 28-37. 23 Jan. 2007 <bioticsresearch.com>.
"Dietary Supplement Fact Sheet: Vitamin D." http://ods.od.nih.gov. 5 Aug. 2005. Office of Dietary Supplements, National Institute of Health. 23 Jan. 2007 <http://ods.od.nih.gov/factsheets/VitaminD_pf.asp
Garland, Cedric F., Sharif B. Mohr, Edward D. Gorham, William B. Grant, and Frank C. Garland. "Role of Ultraviolet B Irradiance and Vitamin D in Prevention of Ovarian Cancer." American Journal of Preventative Medicine 31 (2006): 512-514. 9 Feb. 2007 <http://sciencedirect.com/science>.