It’s not easy admitting that a lifelong passion isn’t all it’s cracked up to be. That’s exactly what happened to Chef Allen Campbell — who years ago, discovered that playing the role of chef came at a cost to his physical and mental health. The result? Campbell switched gears, becoming a consultant and, recently, the personal wellness chef for New England Patriots’ quarterback Tom Brady and his wife Gisele Bündchen. He coauthored his first book with Brady, The TB12 Nutrition Manual,...