"Weller’s doubts began around 2010, when he was researching nitric oxide, a molecule produced in the body that dilates blood vessels and lowers blood pressure.

"Weller’s doubts began around 2010, when he was researching nitric oxide, a molecule produced in the body that dilates blood vessels and lowers blood pressure. He discovered a previously unknown biological pathway by which the skin uses sunlight to make nitric oxide." https://www.outsideonline.com/2380751/sunscreen-sun-exposure-skin-cancer-science https://www.outsideonline.com/2380751/sunscreen-sun-exposure...