Diet that harkens back to prehistoric times

PALEO

Think of a modern eating plan inspired by what hunter-gatherers might have consumed—no processed foods, just meats, fish, and plants.

This clue refers to the "Paleo diet," a modern eating plan inspired by what humans might have consumed during the Paleolithic era—think lean meats, fish, nuts, and vegetables while avoiding processed foods. The word "harkens" hints at looking back in time, and "prehistoric" directly points to the Stone Age, which is the foundation of this diet’s name. It’s a straightforward definition with no wordplay, just a nod to history and nutrition trends.