>There has been some talk about "your body craves a certain mineral so
>you crave arugula". But I want to point out that when we have a food
>intolerance often our body craves that food we are most intolerant of.

This is so true. I  (used to) crave a cheese pizza, and when I ate that,
before paleo, I'd end up practically asleep.

I noticed my dad nods out right after lunch.

Also foreign proteins explain why people feel so sleepy after lunch and
"need" their coffee to wake up again.