You waste a third of an apple if you eat it from side to side, down to the core. An apple core, Foodbeast's Elie Ayrouth argues, is completely edible if you eat it from end to end:
In between bites, Geoff managed, “See, eating it from the sides is wasteful. But if you eat it from the top, the core doesn’t even exist.”
In that moment, Geoff handed the apple back to me. Sure enough, he was nearly halfway through the apple, all without choking on what we normally consider the inedible ‘core.’ Eating from the top allowed more of the pleasant flesh to encompass the surface of every bite.