Uh, if it were just calories, I could just eat icing sugar straight from the packet. That really *would* be inadequate food intake, though definitely easy.

Anyway, the issue with a whole bagel is that chewing a whole unmoistened bagel would be more work than it's worth - it would make me tired of eating long before I'd managed to eat enough fast-burn white processed flour to even slightly fill me up. I suppose I could dip it in water, but the idea doesn't appeal.

Edit: Just realised you said "inside" the bagel. I tend not to eat bagels cut in half and re-assembled because they are too big to put in my mouth comfortably. Which is why biting into an unsliced one is not fun.