When we exercise, even for a few minutes, hundreds of molecules related to our metabolic health rise and fall in our bloodstreams.

Readers discuss coming to terms with body image, and doctors offer their perspectives.

"The damage of this kind of diet is even more visible because of the pandemic," says a Oaxaca legislator who spearheaded a law against the sale of junk food and soda to minors. The idea is spreading.(Image credit: Mauricio Palos/Bloomberg via Getty Images)

Data shows people with certain chronic conditions are more likely to get severe COVID-19 symptoms. Why are they hit harder and what explains the disease's disproportionate affect on African Americans?(Image credit: Bloomberg via Getty Images)