When most of us head to the supermarket, we’re thinking about our grocery lists: Pop-Tarts, Cheez-Its, an 18-pack of Busch Light—the essentials. But Dr. Lewis Dartnell has something else on his mind: survival.

Dartnell, a British astrobiology scientist who penned the book The Knowledge: How To Rebuild Our World From Scratch, recently conducted research on just how long a single adult could survive if stuck inside a grocery store during an apocalypse—zombie or otherwise. His answer: a pretty substantial 55 years.

The scientist and author was specifically speaking to larger stores, but when it comes to the most important items necessarily for long-term survival, non-perishable goods and hydrating liquids, big supermarkets have enough of these supplies to keep an adult alive for over half a century—assuming that adult is alone and doesn’t have to fight off other people with a paring knife he stole from the kitchenware aisle.

However, despite his findings, Dartnell isn’t encouraging people to shack up in their local Publix. Instead, his research was part of a larger look into just how unprepared society might be if something catastrophic was to happen. “Clearly we shouldn’t be worrying 24/7 about a potential apocalypse but it’s interesting to take a snapshot of where we are now and how we’d fare— individually and as a society,” he said. “People’s survival instincts are strong but without a greater focus on Stem (science, technology, engineering and math) skills, the speed at which we’d return to ‘society as we know it’ would be seriously impeded.”