When reading a Mary Roach book, always bring a strong stomach and a sense of humor. Grunt, Roach’s bestselling follow-up to Gulp, is filled with anecdotes about pretty much every aspect of military science that you can imagine. Inside you’ll find a chapter on failed shark repellents, another on surviving IEDs through science, one on stink bombs and weaponized odors, and another where the author offered herself up as a guinea pig to have her sweat collected and analyzed. When covering the horrifying topics of amputations and urogenital wounds, she retains her humor while not being disrespectful to the injured soldiers. If you don’t think you can read a whole chapter about diarrhea, it’s okay to skip it and move on to the next one, but stick around for the poignant ending.