Midway through an almost absurdly indulgent Mediterranean Diet tour of Italy’s Campania region, I had an inconvenient thought. What if, just for a day, I and the half dozen Americans with whom I’d been feasting on prosciutto and buffalo mozzarella, were to experience the Mediterranean Diet the way it was observed by clinicians back when they first “discovered” it in the 1950s?

In this scenario we’d shuffle down the main thoroughfare of Pioppi, past the trattoria where we’d been promised local cheeses, and find ourselves faced with a field of tomatoes, artichokes, and peppers that needed staking and weeding.