Gravel helps keep the floor level and prevents moisture from seeping up. The floor installers are Jean Pierre (left), a mason, and Daniel Shenyi, operations manager for EarthEnable. Courtesy of EarthEnable hide caption

itoggle caption Courtesy of EarthEnable

There's new evidence reaffirming that eating foods with fat€” from avocados and salmon to dairy fat€” doesn't make us fat. eyecrave LLC/iStockphoto.com hide caption

itoggle caption eyecrave LLC/iStockphoto.com

A recent study found a brief delay in peak growth spurt among boys who took ADHD stimulants for at least three years, but no significant effect on their ultimate height. iStockphoto hide caption

itoggle caption iStockphoto

Third-year medical student Allie Tetreault, left, talks with Gabrielle Nuki, 16, at Maine Medical Center in Portland, Maine. Gabrielle helps med students practice patient care. Patti Wight/MPBN hide caption

itoggle caption Patti Wight/MPBN

Barbara Bush helps a nun to fit on a hearing device during a 2012 event in Gulu, Uganda. She says was interested in architecture as a college student but became a global health activist after visiting East Africa with her parents. Reuters/Landov hide caption

itoggle caption Reuters/Landov

Opponents and supporters of a law that restricts abortion in Texas rallied outside the Texas Capitol in Austin as the bill was debated in July 2013. Eric Gay/AP hide caption

itoggle caption Eric Gay/AP

Peter Piot was one of the co-discoverers of the Ebola virus in 1976. "I never thought we would see such a devastating and vast epidemic," he says. Leon Neal/AFP/Getty Images hide caption

itoggle caption Leon Neal/AFP/Getty Images