Why Are So Many People Popping Vitamin D?

Why Are So Many People Popping Vitamin D? – The New York Times (10 articles per month are free)

“Labs performing these tests are reporting perfectly normal levels of vitamin D — 20 to 30 nanograms per milliliter of blood — as “insufficient.” As a consequence, millions of healthy people think they have a deficiency”

Note: Some organizations still think appropriate levels would be above 30 nanograms per milliliter of blood, more details in the text.