I did some searching... "John Jacob Cannell, MD, executive director of The Vitamin D Council, notes that the skin makes 10,000 IU of vitamin D after 30 minutes

I did some searching... "John Jacob Cannell, MD, executive director of The Vitamin D Council, notes that the skin makes 10,000 IU of vitamin D after 30 minutes of full-body sun exposure. He suggests that 10,000 IU of vitamin D is not toxic." https://www.webmd.com/osteoporosis/features/the-truth-about-vitamin-d-can-you-get-too-much-vitamin-d https://www.webmd.com/osteoporosis/features/the-truth-about-...