Endurance athletes like Michael Phelps, here at the 2012 U.S. Olympic Swimming Team Trials in Omaha, can easily burn off stacks of pancakes. Jamie Squire/Getty Images hide caption

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A New York subway ad from Zevia soda company, supporting the mayor's ban. Jason Decrow/Invision for Zevia/AP Images hide caption

itoggle caption Jason Decrow/Invision for Zevia/AP Images

Bacteroides species are some of the most common bacteria in the human gut. Enviornmental Health Perspectives hide caption

itoggle caption Enviornmental Health Perspectives

Cheers! Moderate drinking might slow age-related bone loss in women. /iStockphoto.com hide caption

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Packages of Activa yogurt, which contain probiotics, on a grocery shelf in Chicago. M. Spencer Green/AP hide caption

itoggle caption M. Spencer Green/AP