"What can be estimated is REE, Resting Energy Expenditure."
Not even that, for some of us. My REE is supposed to be 1600
kcal/day. It's obviously less - I'm at 1500 kcal/day intake to keep
my weight steady, and I charge all over the landscape. I've a
neighbour who has to keep her consumption below 1000/day just to keep
from gaining weight from her current 300 lb.
Averages have their limits when applied to human beings. When it
comes to response to inhaled solvents, I've years of experience to
back my estimate that averages don't apply to 15% of us. I've no
reason to believe that our response to nutrients is significantly
different.