General Vitamin D facts and deficiency data:

Vitamin D is a pro-hormone and not actually a vitamin. This is because the body is capable of producing its own vitamin D through the action of sunlight on the skin, while vitamins are nutrients that cannot be synthesized by the body and must be acquired through the diet or supplements. However, sunlight just isn’t enough, nor is diet + sunlight enough for the vast majority of people. Vitamin D deficiency diseases used to be thought of as “rickets” or osteoporosis. Now we know that vitamin D deficiency symptoms are not common, but the diseases produced by inadequate levels of vitamin D are many. Here is the run down on both symptoms and disorders as well as current recommendations for getting your share of vitamin D to stay healthy.


vitamin D deficiency diseases

It is estimated that sensible sun exposure on bare skin for 5-10 minutes 5-6 times per week allows the body the ability to produce sufficient vitamin D.

However vitamin D has a half-life of only two weeks, and most people (unbelievably enough) don’t get this much direct sun. And what was “sufficient” 10 years ago is far from sufficient now.

Recent studies have suggested that up to 75% of adults and children worldwide are vitamin D deficient.

I personally think that this estimate is low if you look at adequate levels of vitamin D. I have not seen a patient yet with adequate levels-not one, and I live in sunny Florida!

Vitamin D is produced when sunlight converts cholesterol on the skin into calciol (vitamin D3). Vitamin D3 is then converted into calcidiol (25-hydroxyvitamin D3) in the liver. The kidneys then convert calcidiol into the active form of vitamin D, called calcitriol (1,25-dihydroxyvitamin D3).

Side not here to statin takers: statins can impair the synthesis of vitamin D.

The Institute of Medicine only recently raised it’s recommendation for vitamin D dosing to achieve a level of 50 ng/ml – with their previous recommendation being a way-too-low 30 ng/ml that some doctors might still be using. The “endpoint of health”, according to the IOM is “bone health” but I’m going to  present some data here to show you it’s a lot more than bones we need to protect with vitamin D and 50 is still “on the low side.” We’ll get into dosing at the end.


Vitamin D deficiency Symptoms:


Rickets or weak, brittle, and defective bone growth


Trouble sleeping or insomnia

Dental decay – too many cavities developing and weak or brittle teeth in general


Vitamin D Deficiency Diseases: Currently not uncommon


Vitamin D plays a major role in the regulation of calcium and phosphorus levels in the blood. These two minerals are the key to maintaining healthy bones; other than magnesium-also important. We need vitamin D to absorb calcium in the intestines and to then reclaim the calcium that would otherwise be “peed out.” In the bones, Vitamin D deficiency manifests as osteomalacia or osteoporosis.

Osteomalacia results in poor bone density, muscular weakness and often causes small micro-fractures of the hips and spine. Osteoporosis is the most common bone disease among post-menopausal women and older men. It affects about 10 million Americans over age 50, even though it is completely preventable.

Cardiovascular disease

Vitamin D is very important for reducing high blood pressure (hypertension), coronary plaquing – meaning atherosclerotic heart disease, as well as plaque- related stroke. Here are some striking statistics. Vitamin D deficiency increases your risk of heart attack by 50 percent. And there’s more- if you have a heart attack and you’re vitamin D deficient, your risk of dying from that heart attack is close to 100 percent!


Several  studies have demonstrated an inverse relationship between blood concentrations of vitamin D in the body and risk of type 2 diabetes. In type 2 diabetics, insufficient vitamin D levels may have an adverse effect on insulin secretion and glucose tolerance. Let me take a moment to remind you that what the labslip says is a normal blood sugar is actually too high. Your doctor may or may not be up to date.

Skin Issues

Vitamin D plays a role in skin cell metabolism and growth. It follows logically then that it has shown some effectiveness in treating itching and flaking which are common symptoms of skin problems from eczema to psoriasis.

Autoimmune diseases

Vitamin D is a potent immune modulator, making it very important for the prevention of autoimmune diseases, like Rheumatoid arthritis and Multiple Sclerosis.


DNA repair and metabolic processes

One well-done clinical study involved healthy volunteers taking only 2,000 IUs of vitamin D per day for a few months. It turns out that they “upregulated” (basically; improved) over 275 different genes that control up to 80 different metabolic processes. These processes included things like improving DNA repair to prevent cancer, decrease oxidative stress, boost the immune system, and much more.

Infections, including influenza

Vitamin D also helps you fight infections of all sorts. A study done in Japan showed that children taking 1,200 units of vitamin D per day during the winter time reduced their risk of getting influenza A infection by about 40 percent.

Miscellanous with studies in progress

Vitamin D deficiency is becoming  scientifically associated with an increased risk of  hypertension, autism, Alzheimer’s disease, fibromyalgia, chronic fatigue syndrome and asthma. But what follows as the final topic is crystal clear.


Previous studies have linked a vitamin D deficiency with colon, breast, lung, and bladder cancer. This connection between vitamin D deficiency and certain cancers was made as early as 1980. In the eighties until close to 2010, studies showed that decreased sunlight was associated with these types of cancers. However, now we have definitive evidence that you need Vitamin D for cancer prevention. A relatively recent study which is an analysis of two well done previous studies quantified the amount of vitamin D needed to reduce cancer risk.

This study, done at the University of California, San Diego School of Medicine demonstrates that higher levels of vitamin D; specifically serum 25-hydroxy-vitamin D, are associated with a decreased risk of cancer. In this study, the research team wanted to pinpoint the blood level of vitamin D needed to effectively reduce the risk of cancer. The marker of vitamin D was 25-hydroxy-vitamin D.

This is also known as cholecalciferal which is what the body utilizes. The scientists pooled analyses of two previous studies of different types: a randomized clinical trial of 1,169 women and a prospective cohort study of 1,135 women. They then combined the two studies and obtained a larger sample size, as well as a larger range of blood serum levels of 25-hydroxyvitamin D or 25(OH)D.


They found that the age-adjusted incidence of cancer was 1,020 cases per 100,000 person-years in one study and 722 per 100,000 person-years in the other. Cancer incidence declined with higher 25(OH)D. Women with 25(OH)D concentrations of 40 ng/ml or more had a 67 percent lower risk of cancer than the women with levels of 20 ng/ml or less. These findings support an inverse association between 25(OH)D and risk of cancer.

The main author of this article says that increasing 25(OH)D concentrations to a minimum of 40 ng/ml in the general population would likely and significantly reduce cancer rates and subsequent mortality. This study confirms that reduced cancer risk is measurable at 40 ng/ml, while additional benefits are seen at higher levels, demonstrating an inverse relationship between vitamin D OH levels and risk of cancer. Subsequent studies put an optimal level of di-hydroxy vitamin D3 between 65 and 70 ng/ml for all symptoms and diseases.

What do you need?

To achieve a level of (minimum) 50 ng/ml to (ideal) 65-70 ng/ml which is the recommendation of A4M  you need 4000-6000 IU/day. That is 50-60 IU’s per pound of body weight- roughly. If you’re obese, you need two to three times more vitamin D. Best is to measure. It’s important to remember that if you’re taking vitamin D supplements, you also need to take vitamin K. The role of vitamin K is to transport calcium into the proper areas in your body, such as your bones and teeth. It also helps remove calcium from areas where it shouldn’t be, such as your arteries. Vitamin K deficiency is actually what produces the symptoms of vitamin D toxicity. You need a 10:1 D to K ratio in your vitamin D supplement.


vitamin d deficiency symptomsYes, of course I think that we should get most of our nutrients from foods. However we are learning more and more about the potential health issues with dairy-the primary source of vitamin D.

Besides, as I noted previously, vitamin D levels which were now know are protective are difficult to achieve with sunlight and diet alone.

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