Vitamin D Facts and Deficiency Data:
Did you know Vitamin D is not actually a vitamin? It is a pro-hormone the body is capable of producing through the action of sunlight on the skin. Conversely, vitamins are nutrients the body cannot synthesize and must acquire through diet or supplements. However, sunlight just isn’t enough, nor is diet + sunlight enough for the vast majority of people. We’re aware vitamin D deficiency symptoms are uncommon, but the diseases produced by inadequate levels of vitamin D are many. Here is a run down of symptoms and disorders as well as current recommendations for getting enough vitamin D to stay healthy.
What is a “normal” Vitamin D Level?
It is estimated that sensible sun exposure on bare skin for 5-10 minutes 5-6x 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 don’t get this much direct sun. Also, 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 this is a low estimate if you look at adequate levels of vitamin D. I have never seen a patient yet with adequate levels and I live in sunny Florida!
Vitamin D production occurs when sunlight converts cholesterol on the skin into calciol (vitamin D3). Vitamin D3 then converts 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).
Note: Statins can impair the synthesis of vitamin D.
The Institute of Medicine only recently raised its recommendation for vitamin D dosing to achieve a level of 50 ng/ml. Their previous recommendation was way too low at 30 ng/ml, and yet some doctors might still follow these guidelines. The “endpoint of health”, according to the IOM is “bone health”. However, the data below will reveal Vitamin D is vital for more than just bones and 50 is still “on the low side.”
Vitamin D deficiency Symptoms: Uncommon
Rickets or weak, brittle, and defective bone growth
Trouble sleeping or insomnia
Dental decay (i.e. too many cavities developing and weak or brittle teeth in general)
Vitamin D Deficiency Diseases: 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. 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.
Vitamin D is very important for reducing high blood pressure (hypertension) and 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. Further, 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!
Studies demonstrate 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. Reminder: When the lab slip shows a normal blood sugar level, it’s actually too high. Your doctor may or may not be up to date.
Vitamin D plays a role in skin cell metabolism and growth. It’s logical that it has shown some effectiveness in treating itching and flaking which are common symptoms of skin problems from eczema to psoriasis.
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 comprehensive clinical study involved healthy volunteers taking only 2,000 IUs of vitamin D per day for a few months. It turns out that they “up-regulated” (improved) over 275 different genes that control up to 80 different metabolic processes. These processes included improving DNA repair to prevent cancer, decreasing oxidative stress, boosting the immune system, and much more.
Infections, including influenza
Vitamin D also helps you fight infections of all sorts. A study in Japan showed 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.
Miscellaneous 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.
we have definitive evidence that you need Vitamin D for cancer prevention.
A Study on Vitamin D Dosage To Reduce Cancer Risk
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 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 suggests 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 a reduction in cancer risk is measurable at 40 ng/ml, while additional benefits are notable at higher levels. This demonstrates 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 roughly 50-60 IU’s per pound of body weight. If you’re obese, you need 2-3x more vitamin D. If you’re taking vitamin D supplements, you also need 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.
Of course, I think that we should get most of our nutrients from foods. However, we’re learning about the potential health issues with dairy which is also, unfortunately, the primary source of vitamin D. Besides, as I noted previously, protective vitamin D levels are difficult to achieve with sunlight and diet alone.