Lots of great questions here today that I'm excited to answer! We talk about heart beats, tumors, creator clash and iDubbbz, the trolley problem, pens, nipples, mastectomies, scratching a mosquito bite, chewing gum as a study hack, getting 8 hours of sleep, night shifts, Advil vs. aspirin vs. Tylenol, why you like the smell of your own farts, holding your breath, David Blaine, consuming salt, and the risks of smoking.