The U.S. Preventive Services Task Force recommends mammograms every other year, while the American Cancer Society endorses annual scans. Kari Lehr/Image Zoo/Corbis hide caption

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Phyllis Omido is one of six winners of the 2015 Goldman Environmental prizes. Goldman Environmental Prize/Courtesy of The Goldman Environmental Prize hide caption

itoggle caption Goldman Environmental Prize/Courtesy of The Goldman Environmental Prize

They don't call him Mr. Toilet for nothing! On a cold and windy November day, Jack Sim visited NPR and gladly struck a pose on his favorite appliance. Note: This toilet was not hooked up. Ryan Kellman and John W. Poole/NPR hide caption

itoggle caption Ryan Kellman and John W. Poole/NPR

Aydian Dowling is currently leading the annual "Ultimate Guy" contest held by Men's Health magazine. If he wins, he will be the first trans man to appear on the cover. Jason Robert Ballard/FTM Magazine hide caption

itoggle caption Jason Robert Ballard/FTM Magazine

Food companies can make safety evaluations of their products in secret without ever telling the Food and Drug Administration. Luciano Lozano/Ikon Images/Corbis hide caption

itoggle caption Luciano Lozano/Ikon Images/Corbis

Liberian workers dismantle shelters in an Ebola treatment center in the Paynes Ville neighborhood of Monrovia. Doctors Without Borders closed the center last month because it was no longer needed. Zoom Dosso/AFP/Getty Images hide caption

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Performance nutrition experts recommend stopping at all the hydration stations for a quick fill-up of a sports drink to replenish the glycogen that's being burned during a marathon. iStockphoto hide caption

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