Not All Cells are Replaced in a Human Body

You Are Not the Same Person You Were as a Child > Contrast > Different Cells are Replaced at Different Rates
Our brain cells are with us for life, contradicting the claim that we are completely replaced every so many years.

 The Brain Uses Lactose During Exercise, but Where Does it...

Lactate, Lactose, and Lactase > Contrast > The Brain Consumes Lactose During Exercise
Lactose is sugar found in milk, lactase is a byproduct of glucose consumption when muscles burn energy. It would make sense if the brain consumed this fuel during exercise, but it consumes Lactose, where does it come from in humans who are mostly Lactose Intolerant?