EDIT: Think about marathon runners: they drink water and electrolytes. I'm pretty sure I can handle a workday fully concentrated without eating every three hours.
Can you handle a marathon on water and elecrolytes each day, every day, for most of your career?
Marathon runners eat during the race
Well, you're better able to digest when you're not constantly running, and you're less reliant on concentration for a marathon.
When I ran an ultramarathon (31 miles) I ate a lot of Oreos during the race. They have snack tables along the route.