Personally, I do not even eat breakfast and rarely lunch.
Drink coffee thats about it.
Hunger (Not Starvation) is the best natural upper. If anything, eat light. If you have the standard "healthy" American breakfast, this is what happens. As you sit down and get ready to trade, most of the blood rushes to your stomach and intestines, hence leaving your brain to operate less efficiently.
I used to eat 2 eggs in the morning, and a container of cottage cheese during lunch, so I never filled myself up and felt a dragdown when the food gets digested. Now I have had a serious lack of appetite just cause personal issues, but I'm very awake in the morning even after 4-5 hours of sleep.
I do not fall asleep during the trading day, but this market has been making me very bored and woozy lately.