3 ms·

Sun exposure. See e.g. https://www.aao.org/editors-choice/sunlight-exposure-reduces-myopia-in-children https://www.aao.org/editors-choice/sunlight-exposure-redu

• LodeOfCode 4y ago
  >study examined the effect of a school-based program encouraging outdoor activities on myopia. "Outdoor activities" is a terrible way to differentiate between sun exposure and large environments