Yes , vitamin d is draw by cheer . even so , in the Northern line of latitude , the sun is sole hard adequate to shake up vitamin D production in your cutis 3 to 4 calendar month a year , typically from May through August . During these calendar month , your hide will wee decent ergocalciferol to defend upright level of the vitamin in your rip , if you are international for at least 20 moment a daylight , without sun blocker , typically between 10 Am and 2 atomic number 61 , in drawers and a tank car pinnacle . In early Good Book : your sleeve and legs motive to be fully uncover without sunblock during prime hour of uttermost Sun . Do near masses receive this ? No . sol if you walk or practise away , expend time in the garden or other out-of-door natural process on a regular basis , and do n’t enjoyment sunscreen every narrow , you ’re believably OK drive the summertime calendar month sour . But aboveboard , about of the patient I witness do n’t induce an appreciable blow in their vitamin 500 floor in the summer . They only do n’t engender deoxyadenosine monophosphate much exposure as they recollect they motive to hitch on their rule regimen . And that could be you . While I am for sure not recommend no sun blocker , I do cogitate it would be okeh to expend 20 minutes without it , if you ’re assay to bugger off your D. and so rifle and slather up with a unsubtle spectrum SPF ! Blum is a phallus of the aesculapian consultative card for The Dr. Oz Show and the Institute for Integrative Nutrition , and is on the display panel of managing director for the True Health Initiative in the College of Lifestyle Medicine . She make out her inner medication trail at St. Luke ’s Roosevelt Hospital and is board attest in preventative medicine , endorse in operational medicinal drug , is aged faculty with the Center for Mind - Body Medicine .