Why do we carve high sugar during exams or tedious memorizing tasks?

Question

Sometimes consuming Hugh amounts of sugar also helps me stay awake and be more focused.

In: Biology

Answer 1

The brain relies almost exclusively on glucose for energy. It can use ketones to a limited extent, but it can’t break down anything complex. (If it did, it would either poison or digest itself.)

Here’s a [more complete answer](https://biology.stackexchange.com/questions/34159/why-is-the-brain-dependent-on-glucose) from Stack Exchange.