Does a good sunscreen affect my absorption of Vitamin D. Well, if you are out in the sun for more than 15 minutes you are going to get enough vitamin D, so you really do not need to worry about that too much, and none of us really use sunscreens as we should: apply a whole shot glass full of sun screen every two hours. You know, so we tend to be a little lax with our sunscreen and that allows us to get enough vitamin D.