In 2009, Dave Asprey posted his first recipe for Bulletproof coffee, a butter-blended, zero-sugar beverage that his company now sells as a convenient store-bought cold brew. You'll notice the brew ...

This week we speak to Dave Asprey, founder of cult US coffee brand Bulletproof. Dave Asprey plans to live until he is 180 years old. No, really, he is being serious. "I don't think it is science ...