Rise of the 'Clean Caffeine' trend is boosting global demand for healthier beverages, offering Thai tea producers the opportunity to expand production and reach international markets.

Michael Pollan laughs and says, yes, he's on drugs while conducting this interview. Okay, he doesn't use those exact words, but he acknowledges that he has a "tall, takeout container" of half-caff coffee at his side as we discuss, via phone, his latest project, simply titled "Caffeine," available only as an audio book from Audible.