Tuesday, December 2, 2008

Vitamin D: Fights Fat and a Whole Lot More!

Vitamin D is everywhere. You hear about it on the news, in magazines, even right here on empowher.com. Some tout it as the new super vitamin yet why are so many Americans deficient? It is fortified in milk, bread, cereals, and the sun right above our heads (unless you live in Portland like me) yet studies show even those living in the brightest spots are not receiving enough.

So let’s review…what is Vitamin D?

First of all, it is a fat soluble vitamin that is metabolized by ultraviolet light (particularly UVB) or from our diet. Vitamin D is taken into our liver where it is converted into 25(OH) Vitamin D3 (calcidiol) which is the major form in our body and the kind that we test. To become biologically active, it goes through an extra step in the kidneys where it turns into 1,25(OH) Vitamin D3 (calcitriol). This active form only hangs around for about 6 hours where as the testable form remains up to 2 weeks. Additionally, once activated, Vitamin D becomes a hormone.

But, Dr. Jones, I am a sun-bunny! I live for its’ warmth and love to be tan. Of course, but sunscreen with a SPF 8 and above eliminates 93-99% of your vitamin D absorption. This is why those living in Florida and southern California are depleted. The same holds true for people with darker pigmented skin. Melanin blocks absorption as well.

What does it do?

1) Vitamin D has a major role in calcium and phosphorus balance. This, of course, means we need enough to improve bone health, reduce fracture risk, and reduce bone pain.

2) It helps your body manage an autoimmune disorder such as rheumatoid arthritis, multiple sclerosis, lupus, and others.

3) There are receptors in the heart muscle so that it improves heart contractions and vascular tone. There are links to low levels and myocardial infarction risk.

4) It is important to your renin-angiotensin-aldosterone system which helps monitor blood pressure, electrolytes, and water balance in your body.

5) Vitamin D is potentially anti-cancer! There are receptors in your colon, brain, breast (and prostate for you male readers). Quoting directly from the research, “It has been documented that patients with the highest serum vitamin D levels had a 50% reduced risk of breast and colorectal cancer. A serum level of 52 ng/mL was associated with the greatest risk reduction of breast cancer. In colorectal cancer, it has been found that a serum 25(OH)D level of 34 ng/mL can reduce the incidence by half, and at serum levels of 46 ng/mL, the risk of colorectal cancer can decrease by two thirds.”
Wike-Malone R, Kessenich C. Vitamin D Deficiency: Implications Across the Lifespan. J Nurse Practitioners. 2008;4(6):448-456.

6) Sufficient levels are needed for those with periodontal disease in order to preserve the health of your teeth.

7) Feeling moody? There is an association between low vitamin D and PMS, seasonal affective disorder (low mood in the winter), and depression.

8) Sore Muscles? There are receptors in the muscles for vitamin D. Some patients with a fibromyalgia-like picture are actually deficient in this nutrient!

9) It is good for brain health. Migraine sufferers and epileptics have been shown to have low vitamin D values.

10) It helps fight fat! Lower vitamin D levels are associated with increased body fat in both the visceral and subcutaneous areas.

I highly recommend you request your 25(OH) Vitamin D3 levels are tested every year. The current recommendation for “sufficient” is above 30ng/ml. The research recommends higher than 50ng/ml for helping autoimmune disease and reducing cancer risk. Anything over 100ng/ml is considered too high.

Make sure you take your vitamin D3 (also known as cholecalciferol) with some fat for better absorption. Do not take it with your heartburn medication or any weigh-loss medications that blocks fat – this will reduce your vitamin D absorption.

According to the National Institute of Health, Office of Dietary Supplements, the current recommended daily allowance (RDA) of Vitamin D is 200-600 IU/day depending on your age. If your levels are low, you may need to temporarily increase this amount to 1000-4000 IU/day or more however, please make sure you are under the supervision of your doctor and repeating your vitamin D test every few months to see that your levels are increasing. Once you have reached your vitamin D goal, you can back off your dose.


References:
1.Wike-Malone R, Kessenich C. Vitamin D Deficiency: Implications Across the Lifespan. J Nurse Practitioners. 2008;4(6):448-456.
2. Murphy P, Wagner C. Vitamin D and Mood Disorders Among Women: An Integrative Review. J Midwifery Womens Health. 2008;53(5):440-446.
3. Hicks G, Shardell M, Miller R, et al. Associations Between Vitamin D Status and Pain in Older Adults: The Invecchiare in Chianti Study. J Am Geriatr Soc. 2008;56(5):785-791.
4. Wheeler S. American Headache Society 50th Annual Scientific Meeting: Abstract S33. Presented June 28, 2008.
5. Karakis I. American Epilepsy Society 61st Annual Meeting: Abstract 3.337. November 30-December 4, 2007
6. Kremer R. Vitamin D Insufficiency Linked to Increased Body Fat. J Clin Endocrinol Metab. Published online November 4, 2008.
7. Office of Dietary Supplements: http://ods.od.nih.gov/factsheets/vitamind.asp#h9