
Meaty product contains higher % of tryptophan.. an aminoacid
that can be converted to serotonin (a neurotransmitter) which makes
you feel good.
Chocolates makes you feel good... because of tryptophan too,
which in turns converted into serotonin.
Coke and sugary drinks contains high amount of carbohydrates,
when digested in body it becomes glucose~ You will feel great after
drinking coke because of the increase in blood glucose.

Salad and vegetables are food that is considered low GI. Low GI
food release glucose slowly. That's why you wouldn't feel sooo
happy eating salad....