A thousand calories of peanut butter is one cup, 8oz, of peanut butter.

Maybe 4 or 5 good spoonfuls.

I'm willing to bet that almost any healthy adult could down 4 spoons of peanut butter w/o issue, and that most people would end up being way over their calorie limit for the day as their body wouldn't go "yup that was lunch and half of dinner! All good now!"

The quantity given was in calories, about 1/2 of what you need in a day. Yes PB is heavy, yes that amount should register.

Drink a glug of olive oil. You'll probably be very regular on the toilet the next day, but your body will still ask for more calories, despite the 500+ you just consumed.

4 spoon fulls of peanut butter may or may not register. That many calories in a very short time frame often does not.

I take shots of OO regularly. Stops hunger but slowly, because it takes a while for body to convert to fat metabolism.