I rarely go out in the sun, life hurts to much to do much of anything let alone sit outside. But, my GP gave me a wonderful tip. She said even sitting in the car with the window down when your sat idling at the lights or various intersections waiting for your cars chance to move can allow enough sun through to reach our body. We don't have to be out under the sun rays, reflected sunlight will do just as good a job. Even sitting by a window inside the house can have added benefit.