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Vitamin D Deficiency


A large number of studies, such as http://www.ncbi.nlm.nih.gov/pubmed/18076342, have found that vitamin D deficiency is likely the rule.

This is an important fact and bears repeating:

Vitamin D deficiency is so common that it's likely the rule.


In this article, we will be looking into the following:

  • the pervasiveness of vitamin D deficiency in our world;
  • factors increasing the risk for being vitamin D deficient;
  • examine the ranges of vitamin D blood levels and what it means; and
  • how to determine your own vitamin D blood levels.

The Pervasiveness of Vitamin D Deficiency?

According to recent vitamin D studies, your chances of being vitamin D deficient is high.

Consider the following facts:

  • Several studies conducted in sunnier parts of the globe (Lebanon, India, and Turkey) found that 30%-50% of children were vitamin D deficient.

  • In his practice, vitamin D expert Dr. Goram Khalsa estimates that 75% of his new patients are vitamin D deficient.

  • An estimated one billion people worldwide have insufficient or deficient levels of vitamin D.

Factors That Increase Your Risk For Becoming Vitamin D Deficient

1. Lack of Sun Exposure

We all know exposure to the sun increases our risk of skin cancer. Since the late 1980's doctors, and other professionals alike, have been screaming at us to stay away from the sun, and to wear sunblock if we do play in the sun. A recent groundbreaking study conducted in 2009 by the Nutrition and Health Research Center (SUNARC) suggests that if Americans double their exposure to solar UVB they would avoid almost 400,000 deaths per year, while only a suffer a few thousand extra deaths from skin cancer and melanoma!

According to this study, it seems to suggest that overall mortality rates would decrease, not increase, with more exposure to the sun. In other words, the pros of playing in the sun significantly outweigh the cons.

If you want to read more about this study, it's "Study #2" in Top 10 Vitamin D Studies.

There are other studies found that people living in higher latitudes are at higher risk for developing non-skin cancers than those living in lower latitudes.

Sun exposure dramatically increases our vitamin D levels. Just 15 minutes in the sun will provide you with 10,000-15,000 IU of vitamin D.

2. Dark Skin

People with darker skin have more melanin in their skin, which is a skin pigment that absorbs ultraviolet radiation, ultimately limiting the production vitamin D. Melanin is like a natural sunblock.

3. Season

You have a much higher chance of having a vitamin D deficiency in the winter than you do in the summer.

Studies have discovered that people diagnosed with vitamin D-related cancers (prostate, breast and colon) are more likely to survive if they were diagnosed in the summer rather than the winter.

4. Wearing Concealing Clothing

Our ancestors walked around the equator naked all-day everyday. In most of today's developed nations, walking around naked will likely get you arrested. Obviously, cothes block the UVB rays, which limits the vitamin D you get.

5. Elderly

It's estimated that over half of elderly Americans (65 years of age and older) are vitamin D deficient. Actually, several studies indicate the range of vitamin D deficiency in the elderly in North America and Europe range around 40%-100%!

As we get older, our bodies become less and less efficient at metabolizing vitamin D. An elderly person would need to spend 400% more time in the sun to get the equivalent amount of vitamin D a young person would get.

Vitamin D plays a big role in calcium's ability to build and maintain strong bones. Given this fact, it's not surprising that elderly people who are vitamin D deficient have a higher incidence rate of bone fractures and osteoporosis. To reduce their risk of these bone fractures, the elderly should strive to keep their vitamin D levels above 30 ng/ml.

6. Exclusively Breast-Fed Children

Newborns that are exclusively breast-fed are at a higher risk of vitamin D deficiency. The reason for this is that breast milk typically contains about 20 IU of vitamin D per liter. For mothers to give their babies a sufficient amount of vitamin D, they need to keep their vitamin D blood levels above 40 ng/ml (no lower than 30 ng/ml).

Infants that are vitamin D deficient are at a higher risk for rickets.

Vitamin D Levels

Less than 10 ng/ml: Severe deficiency
10-20 ng/ml: Deficiency
20-30 ng/ml: Insufficiency
30 -40 ng/ml: "Normal"
40-70 ng/ml: Optimal
Over 100 ng/ml: Overdose
Over 150 ng/ml: Toxic

Note: Most researchers use "ng/ml", which stands for "nanograms per milliliter"; however, another acceptable unit of measurement is "nmol/l", which stands for nanomoles per liter.

1 ng/ml = 2.5 nmol/l

Example, let's say you took a vitamin D test and it showed that your vitamin D level was 32 ng/ml. To convert this to nmol/l, multiple 32 by 2.5. So your blood levels in nanomoles per liter would be 80 nmol/l.


How to Determine Your Vitamin D Levels

There are two ways to find out your vitamin D levels.

Your first option is to go to your doctor and ask for 25-hydroxyvitamin D (25D) test.

Your second option is to get a self-test kit called a Blood Spot home test.

This test is similar to a blood-sugar test in that you need to prick your finger to draw a small sample of blood; however, you don't get your results back immediately. You will need to send the blood sample to the laboratory. You should get your results back within a few weeks.

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