The best time to get sunlight to produce Vitamin D in the body In order to produce maximum vitamin D in your body, you should soak yourself between 10 am to 3 pm. At this time, your body get powerful UVB rays that help produce sufficient vitamin D. However, the more exposer to the sun can harm your body. So it is necessary to follow expert’s advice. According to the Vitamin D Council, 15 minutes sun exposure are enough for people with light color skin, while people with dark color skin require 1 hour sun exposure to get maximum vitamin D.