Have you run into this issue? What are the most effective ways you've found to reset your brain so it feels as fresh as it does when you wake up?
There are some shortcuts you can take in the short term. One is caffeine (which requires large doses if you have a tolerance, will prevent focus if you overdose, will make you crash hard eventually, and will interfere with the sleep you need to be properly refreshed and focused.)
Another is amphetamines (all the downsides of caffeine, plus longer term negative effects, plus legal issues. TL;DR: really bad idea).
Sugar is... well, on HN it's almost political. But let's stick with the non-controversial claims like the fact that it'll make you crash pretty quickly; will cause weight gain if you're not cutting back proportionally on calories elsewhere; and that too much of it can cause diabetes.
There is one substance that I recommend ingesting that can perk you up a bit: water. Even mild dehydration can cause brain fog and low energy. And ok, it's technically possible to consume enough of the stuff to cause negative side effects other than the need to pee. But most of us find it difficult to consume that amount if we tried.