An epidemic of vitamin D deficiency in the Northern Hemisphere has been ignored for years. An endocrinologist recommended ergocalciferol 50,000 units three times a week for four to five weeks. If retesting shows improvement, dosing can be decreased to 50,000 units once a week. Alternatively, patients can be given OTC vitamin D 1,000 IU twice daily for a month. When is the best time to test for this deficiency? Is there any way to determine the reliability of OTC forms of vitamin D?
—Dawn Shafer, FNP, Floodwood, Minn.
The body’s production of vitamin D has long been known to result directly from exposure to sunlight. Logic dictates that the less sunlight we live with, the lower our vitamin D levels become. This can be a result not only of climate and geography, but also of decrease in outdoor activities. Interestingly, a study involving elderly residents in Florida showed a seasonal variation in serum vitamin D levels of 13%-14% even in this sunny environment.
Testing methods are usually standardized by the laboratory used. The timing of the test may show some variation but not enough to sway the need for supplementation.
Management of any deficit can take several approaches, but most endocrinologists agree that simply increasing exposure to sunlight will not suffice since patients are likely already in a deficient state. Replacement methods, such as the one mentioned, are well-grounded. Before the body can begin normal, homeostatic use of vitamin D, the empty store must be refilled.
The best way to determine quality of OTC products is to research the suppliers’ policies and review their statements of quality control and manufacturing processes. If these are not adequately reported, avoid the product.
—Sherril Sego, MSN, FNP (112-17)