Question on Vitamin D

Dear Dr. Spence,
How important is vitamin D? Don’t I get enough from my diet?
Signed,
Dee Dee

Dear Dee Dee,
Vitamin D is critically important in maintaining healthy bones, this much is clear. It is estimated that one billion people worldwide have a vitamin D deficiency. Amazingly, a study at a Boston hospital found a whopping 32% of healthy students, residents and physicians were vitamin D deficient despite intake of multi-vitamins and a glass of milk per day! Most vitamin D is obtained from sun exposure (3000 IU per exposure of 10 to 15 minutes) versus dietary sources (one cup of milk = 100 IU). Recent data suggests that most women should ingest 800 IU per day, whereas previous recommendations were set at 400. Many patients diagnosed with osteoporosis actually have vitamin D deficiencies. Bisphosphonates like fosamax will not treat osteoporosis in these cases and may actually lead to severe low calcium levels. It becomes increasingly important that any patient diagnosed with osteoporosis be screened for vitamin D deficiency. Most patients can supplement with 800 to 1000 IU per day to help maintain normal levels, but those with malabsorption may require 25,000 to 50,000 IU per week. So what? We know that supplementation of vitamin D may help prevent osteoporosis, but more recent studies show it may decrease the risk of falls in elderly populations and may decrease cancer rates. A study of 1180 women older than 55 years of age revealed that supplementation with 1000 IU of vitamin D plus calcium decreased the risk of cancer by roughly 35%. The number needed to treat to prevent one case of cancer is only 21 with an absolute risk reduction of 5%. Not bad for something as simple as vitamin D, which generally has minimal, side effects, even at massive doses. Update on peripheral vascular disease (PAD): A German trial of 6880 patients greater than 65 years of age revealed a five year mortality rate of 19% in those with PAD. None of those patients had symptoms! The rate rose to 23% in those with symptoms; a very small, insignificant difference. The bottom line: PAD carries a poor prognosis regardless of whether a patient has signs or symptoms of leg pain or not. Mortality as a whole is increased by 60-80% in patients with PAD. Recommendations by the German authors are that all patients older than 70, or those aged 50-69 with cardiac risk factors, should be screened. Not a bad idea given the relative low cost, good insurance coverage, and ease of testing.

Do you have any medical questions or concerns that you would like addressed? You can contact Dr. Spence by email at panhandledailydose@hotmail.com or by mailing your question to Daily Dose, P.O. Box 6107, Marianna, FL 32446.