Causes of low vitamin D levels

In this article I want to write about some of the possible causes of low vitamin D levels, but this is really common today and may be contributing to a large part of our health problems and increasing chances of diseases like heart disease and cancer.

The Vitamin D Council recommends aiming for 50-80 ng/ml blood levels for optimal health. Anyone with under 30 ng/ml can be considered deficient and should take action as soon as possible, either increasing their sun exposure or start supplementing.

Our primary source of Vitamin D is production from cholesterol in the skin when it is exposed to UVB Rays. During evolution we were exposed to the sun pretty much all day, so Vitamin D deficiency was not a problem back then.

These are the main causes of low Vitamin D levels:

1. Lack of sunlight:

In modern times, we don’t get much sun unless we live close to the equator and get sun exposure throughout the year. Even those who live close to the equator probably stay inside most of the day, or drive around in cars where the glass shields them from the sun. People have even started using sunblock in order to avoid skin cancer, but at the same time they destroy their number one source of Vitamin D.

This cause is even more common in people with dark skin, because they produce much less Vitamin D for the same amount of sun exposure as fair skinned people.

2. Lack of Vitamin D from diet:

There are some foods that contain Vitamin D and the best source is cod fish liver oil, a tablespoon can contain more than 1000IU of the vitamin. The other primary source of Vitamin D is fatty fish.

The problem is, if you get next to no sun, you would have to eat ridiculous amounts of those foods in order to achieve optimal Vitamin D levels.

3. Poor absorption:

If your diet contains gluten and you are sensitive to it, then your absorption of vitamins is going to be poor and your chances of deficiency greater, and this applies to other nutrients as well. Another thing that a high gluten diet can do is reduce the half-life of Vitamin D in your bloodstream, therefore making you burn even faster through the little that you have. Read my article on what you need to know about Gluten for more information.

These are the three main causes of low Vitamin D levels, and if you think you don’t get enough sun then you should consider supplementing with it. Where I live, in Iceland, we get next to no sun during the entire year, so I take about 5000 IU per day, bringing me to about 6000 IU total when I factor in my daily tablespoon of cod fish liver oil.

This is a great video that summarizes some important points about this very important vitamin:

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  1. My daughter has cereatic Atheritis, and takes embril can that cause her vitiamin defisency? I am very concerned for her what can I do besides a suppliment?

  2. My mother was just prescibed vitamin d (ergo) 50 000 iu ca pliva 2 times a week due to a count of only 5.0 She is 74 and is now experiencing leg cramps. She has only been taking this 2 weeks. Is this common? What can she expect in the future while taking this – More intense cramping?
    Thank you for your help :)

  3. Francine Sterud says:

    Does low Vit D have anything to do with high cholesterol? And what does low Vit D have to do with primary hyperparathyroidism? And If you have low Vit D and normal calcium what does that mean?

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