For years health care providers have been sounding the alarm on low vitamin D levels among black folks, equating the deficiency to a "hidden epidemic" that could be connected to elevated cancer rates and other health problems.  But according to a new study in the New England Journal of Medicine, doctors may have been misdiagnosing many black patients with vitamin D deficiency, due to genetic differences in blood types between white and black people. The blood test most commonly used to determine this particular vitamin deficiency doesn’t account for a unique protein found among many black people, and researchers say this genetic traits can be traced back to African ancestors.

(h/t NPR Health)