I often get headaches from eating raw beef, and they are always in the morning.
I fix it with organic coffee because I don't eat in the morning, however the cause has always been not enough fat, so I think of them as low-fat headaches.
"This trouble is worse for the forest Indians who depend at times on rabbits, the leanest animal in the North, and they develop rabbit starvation. This leads to headache, lassitude, a vague discomfort, and diarrhea."
I don't get the diarrhea.