This Is Why Grandma’s Cooking Sticks With You

Deja Vu All Over Again: There’s a reason a cookie baked using your grandma’s famous recipe can take you right back to her kitchen, even years later. Food memories tend to hit differently than other types of memories — they’re often more vivid and harder to shake. But new research is beginning to explain exactly why that is.  

The Study: The vagus nerve is the main line of communication between your gut and your brain. USC researchers wanted to know if it also plays a part in memory, so they tracked brain activity in rats while they ate. Nutritious food triggered a rise in acetylcholine, a chemical tied to memory formation, in neurons feeding into the brain’s memory center. When the researchers cut off communication along the vagus nerve, that rise disappeared, and the rats struggled to remember where they’d found food.

The Takeaway: Your body may reward foods that nourish you by making those meals stick in your memory, not just because they taste amazing.

Keep in Mind: This research is in rats, so it’s unclear if the same pathway works in humans. The study also found a steady junk food diet weakened this connection over time.