In Caffeinated, Carpenter strives to answer how caffeine has become ubiquitous and how that affects Americans today. He attempts to understand how consumption of this largely unregulated drug can help or harm through amount (and form) consumed, addiction and restraint. However overall, this book falls short of its ambitious premise. There are fascinating insights backed by research scattered through the pages highlighting the history, however it fails at focusing within each chapter and across the entire book. Caffeinated is recommended for the interesting tidbits but be warned you may walk away with more questions than answers.