OH GOODNESS. My bad.
http://www.grassrootshealth.net/ not grassroots.org
I never wear sunscreen (don't tell Tina) unless I am deliberately going to be in the sun more than a couple of hours (sunning, going the beach, etc.).
I'm rarely outside during the middle of the day during the week except to walk to/from lunch on some days and at that only my face & arms are exposed. Apparently the morning or late afternoon sun when walking the dogs is not sufficient exposure. Plus, over 40 we just don't make Vit D as well from the same exposure as when we were in our teens and twenties.
I'm rarely out in the sun for any length of time on the weekends either - no yard so no yardwork, no garden, no soccer or baseball games to attend, none of that sort of thing. I'm a prime #1 candidate for deficiency, and I am deficient.