C.D.
Welcome to the world of terrible twos. Many think that you have to be 2 for the terrible 2's, but they can start earlier, as is your case. My older son started terrible 2's at 16 months as well, so I feel your pain. What we did at that age to redirect was to always go to him and bend down to his level and hold his hitting hand and say firmly to him "no. No hitting" The key to this and any form of discipline is consistency. Do this every time, and it will end eventually.
My older son still doesn't eat much (he's 4.5 years old), so I don't have many ideas there. My only thought is to give him a snack at snack time that he can walk around with while he is enjoying his new world. If he is hungry, he will eat. I wouldn't worry too much about this at this time. He won't starve, and you will probably go nuts worrying about this and his terrible two behavior.
Hang in there! It does get better.