"The cool thing about this gas we're using, hydrogen sulfide, is that it isn't something manufactured that we're taking down from a shelf -- it isn't 'better living through chemistry' -- it's simply an agent that all of us make in our bodies all the time to buffer our metabolic flexibility. It's what allows our core temperature to stay at 98.6 degrees, regardless of whether we're in Alaska or Tahiti," Roth said.