There are many reasons why it's not that simple. 1. We need to dress up to go outside, exposing only minimal amounts of skin. 2. People of color produce less

There are many reasons why it's not that simple. 1. We need to dress up to go outside, exposing only minimal amounts of skin. 2. People of color produce less vitamin D (most likely due to skin pigmentation). 3. Pollution and shadows significantly reduce UV light within cities.