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Patient asks: I have been taking vitamin D for a long time and my levels are still low. Why?

There are many possible reasons. First, normal levels of vitamin D are measured by a blood test called 25(OH) D, or 25 hydroxy vitamin D, and should be between 30-100. Patients may be told by their mainstream doctors that their levels are normal at say 35. Functional medicine doctors would say 35 is low functional range and is preferable at say 70. So how much vitamin D should one take? In our region, North east America, we need more vit D in the winter than in the summer. Taking only 1-2000 IU will not suffice, and 5-7000 IU daily would be recommended.

Also important is what form of vit D is taken. Is it D2 (ergocalciferol) which is less bio-available than D3 (cholocalceferol). Unfortunately, D2 is still commonly prescribed by mainstream doctors, as a huge dose, 40,000 IU weekly; not very efficient.

Another reason for chronic low levels is malabsorption. Certain medical conditions that cause fat malabsorption such as celiac desisease, Cohn’s disease, cystic fibrosis, gastric bypass, make fat soluble vitamins such as vit D less bioavailable.

Liver or kidney weakness, caused by many factors including consuming junk foods and chemical laden foods and drinks, cause difficulty in converting calcitriol, the active form of vit D.

Overweight, obese people have less circulating vit D availability because vit D is sequestered by fat cells.

Certain medications, statins for lowering cholesterol, anti-convulsants, gluco-coriticoids, anti-rejection meds, and anti-retroviral meds may activate the destruction of vit D.

Studies show an incredible array of conditions that might be helped when optimum vit D levels are maintained. The possibility of reducing colon cancer by 50%, breast and ovarian cancer by 30%, prevent or alleviate osteoporosis, hypertension, cardio-vascular disease, depression, epilepsy, type 1 diabetes, migraine headaches, autoimmune disease, PCOS, muscle and bone pain, psoriasis, rheumatoid arthritis, inflammatory bowel disease, and more.

Since vit D testing through blood has become more widespread the deficiency of vit D seems epidemic in proportion. A report from a Massachusetts inpatient facility showed 57% of 290 patients’ vit D deficient. Another study out of Minnesota showed 93% of 150 patients vit D deficient…. 48% of patients with multiple sclerosis(MS), 50% with lupus, 42% of healthy adolescents, 62% of morbidly obese, 83% of low-back pain sufferers, 58% of Japanese girls with Grave’s disease etc.

Dr. Grant on his web site demonstrates with the use of NASA space satellite images that the incidence of cancer and MS mimics the pattern of lower sunlight exposure, and lower vit D levels. One study out of Creighton University in Nebraska, published in 2007, showed a remarkable reduction in cancer incidence – about 60%, in 1200 women, by those taking vit D, vs. those not.

Though here in the U.S. we are spending enormous amounts on fancy interventions such as heart bypass surgery and organ transplants, Etc., and enormous amounts of medications are consumed by all strata of society, measurements of health are far lower here than in other countries spending far less. Vitamin D testing and supplementation for the whole population is a solution which is guaranteed to improve overall health at a ridiculously low cost, and with no harmful side effects.