Vitamin “Hormone” D is an amazing vitamin responsible for a multitude of physiological functions in your body.  And it seems that this potent energizing cancer-protecting “pro hormone” is epidemically low across the population.  Let’s explore this underestimated vitamin that is making a epic return to the forefront of medicine, why it’s important, and why most people have low levels…

We Are Not Producing Enough Vitamin D

The Centers for Disease Control and Prevention estimates that more than 180 million Americans, or 60 per­cent of the population, are Vitamin D deficient.  And it is easy as either getting out in the sun or taking a supplement when sun exposure is not possible.  But, fear of malignant melanoma, the fatal form of skin cancer, keeps most people out of the sun avoiding all the amazing benefits. The truth is that the incidence of melanoma continues to increase dramatically although many people have been completely avoiding the sun for years.[i]  This does not mean to advocate sun burning, which is always a bad idea.  However, safe sun exposure allows you to make Vitamin D properly at the skin level and ultimately optimizes your health.

A recent study in the Journal of the National Cancer Institute[ii] actually showed a correlation with increased sun exposure to lowered death rates in people diagnosed with the skin cancer melanoma.  The authors proposed two possible hypotheses as to why this may be:

  1. Sun exposure creates vitamin D which has properties that prevents cancer cells from proliferating and also leads to their destruction, called apoptosis.
  2. Sun exposure increases the amount of melanin or pigment in the skin which increases DNA repair capacity which would reduce the amount of mutational and cancerous changes within a melanoma.

I would like to propose an additional, although not as cogently scientific of a statement:  The Sun is good for you!  I truly believe this is an obvious, natural statement.

Benefits of Vitamin D

  • Maintains Your Calcium Balance
  • Prevents Osteoporosis[iii]
  • Potent immune system modulator.[iv]
  • Has a Role in Insulin Secretion under conditions of increased insulin demand.[v]
  • Blood Pressure Regulation[vi]

How much sun exposure is good for me?

Dr. Michael F. Holick of Boston University School of Medicine and other experts recommend figuring out how long it takes your skin to get pink, then expose ¼ of your skin (ie face, arms, legs) for ¼ of that amount of time during the hours of 11 am to 3 pm.  So, most Caucasian people will only need 5-10 minutes per day during that time.  Darker pigmented Caucasians and darker pigmented people such as those of East Indian or African descent will need up to an hour in the sun to achieve the same results.

Within 30 minutes of full body exposure to the sun most people will make at least 10,000 units of vitamin D.[viii]

Testing Vitamin D Levels & Vitamin D Toxicity

For basic health reasons and to optimize your health, you should have your Vitamin D levels checked.  The best test to determine this is the “25 hydroxy (OH) Vitamin D” level, which shows the actual stored amount of Vitamin D that is ready to convert into the active form called 1,25 hydroxy Vitamin D.  Some doctors are still using the outdated 1,25 hydroxy (OH) Vitamin D test that is essentially useless.

  • Optimal levels should be between 50 ng/mL and 80 ng/mL.
  • Remember:  Sonora Quest currently uses the Mass Spectometry test which makes the results come back too high.  Be sure to multiply the 25(OH)D3 value by 0.6 to yield the correct value.
  • Lab Corp uses the Diasorin test which is more accurate.

 

Supplementing with Vitamin D:  How much Vitamin D should I take?

First, you need to make sure you are supplementing with Vitamin D3 or cholecalciferol.  Avoid products that have Vitamin D2 which is not as effective as D3.

Basic guidelines for Vitamin D3 dosing:

  • Healthy children under the age of 2 years:  1,000 IU daily
  • Children over the age of 2:  2,000 IU daily
  • Adolescents and adults: 5,000 – 10,000 IU daily

A Few Cautions:

  • Remember to monitor your vitamin D levels using the 25 OH Vitamin D blood test after about three (3) months from starting the vitamin D supplementation.
  • The following medications increase the metabolism of vitamin D and may decreaseserum D levels:
    • Phenytoin (Dilantin), fosphenytoin (Cerebyx), phenobarbital (Luminal), carbamazepine (Tegretol), and rifampin (Rimactane).
  • The following medications should not be taken at the same time as vitamin D because they can decreasethe intestinal absorption of vitamin D:
    • Cholestyramine (Questran), colestipol (Colestid), orlistat (Xenical), mineral oil, the fat substitute Olestra, and ketoconazole.

 

Food Sources of Vitamin D

It is always good to get additional vitamin D from food sources, particularly in the winter when sun exposure is more difficult.

Fish liver oils, such as cod liver oil, provides an easy, inexpensive, whole food option to obtaining Vitamin D.  One tablespoon or 15 mL provides about 1,360 IU of Vitamin D.  Be sure that you are using a reputable brand of oil such as Nordic Naturals® or Carlson’s®, among others.  Cod liver oil should not be “fishy” and most reputable brands are actually very tasty.  Most sources of cod liver oil are not like grandma’s in terms of taste, but remember that grandma knew what she was doing when she was giving you your cod liver oil.

Caution:  Do not take in excessive amounts of cod liver oil.  Keep the dose at no more than 1-2 tablespoons daily.  The vitamin A content of cod liver oil is variable and can become toxic in large amounts.

Fatty fish species, such as as herring, provides about 1383 IU of vitamin D for every three ounces of fish.  Salmon and tuna also provide vitamin D, but the amounts are much lower.


[i] Hemminki K, Zhang H, Czene K. Incidence trends and familial risks in invasive and in situ cutaneous melanoma by sun-exposed body sites.  Int J Cancer. 2003 May 10;104(6):764–71.

[ii] Journal of the National Cancer Institute, Vol. 97, No. 3, February 2, 2005

[iii] Heaney RP. Long-latency deficiency disease: insights from calcium and vitamin D. Am J Clin Nutr 2003;78:912-9

[iv] Griffin MD, Xing N, Kumar R. Vitamin D and its analogs as regulators of immune activation and antigen presentation. Annu Rev Nutr. 2003;23:117-145.

[v] Zeitz U, Weber K, Soegiarto DW, Wolf E, Balling R, Erben RG. Impaired insulin secretory capacity in mice lacking a functional vitamin D receptor. FASEB J. 2003;17(3):509-511.

[vi] Sigmund CD. Regulation of renin expression and blood pressure by vitamin D(3). J Clin Invest. 2002;110(2):155-156.

[vii] Available:  www.vitamindcouncil.org

[viii] Holick MF. Environmental factors that influence the cutaneous production of vitamin D.  Am J Clin Nutr. 1995 Mar;61(3 Suppl):638S–645S.