5 Things That Increase Your Risk of Vitamin D Deficiency
If you meet any of these criteria, chances are you're not getting enough D.
You live north of 34 degrees latitude.
"From October through March, the angle of the sun is so low that we just can't produce any D from it," says Joan M. Lappe, PhD, a researcher and professor at Creighton University. Only those living south of 34 degrees (imagine a line running from Los Angeles to Columbia, South Carolina) get enough UV-B rays year-round.