Coffee diet woos Americans with 'Bulletproof' pledge

A new coffee diet claiming to help lose weight and improve IQ is gaining a major following in the United States -- and raising eyebrows among doctors skeptical of its benefits. Dave Asprey, the founder and CEO of the "Bulletproof Diet," pulls no punches when making claims for his radical health recipe, cup of coffee in hand. The cornerstone of Asprey's diet is a drink called Bulletproof Coffee, a modified version of the caffeinated beverage which uses beans stripped of mycotoxins -- essentially