[caz223]

I have kind of a double whamy here.
I'm allergic to certain foods (Heartbeat hits 220+).
When your heart's cruisin', your breathing is so shallow and erratic, you won't be able to regulate it enough to shoot effectively. Food items have different effects on different people. For goodness sake, stay away from known stimulants or depressants the day of, and if known, the day before at a minimum. I'm sure you're aware of your heartbeat, pulse and BP during extreme focus, but get a heart monitor and play with it at the range. Calm and relaxed is best. Your control and focus is better when you're relaxed. You can't relax if you're chemically stimulated. You can't focus if you're chemically depressed. Without focus and fine motor control your shooting will be in the potty.

I also have blood sugar regulation problems. I go for 12+ hours without food=BAD. I get shakes randomly, depending on my activity level, carb count of last meal, stress, and mental focus. If I can focus for a minute, my shakes go away. The problem is, I can't focus when I'm low on sugar.
I suspect many people have sugar problems and they don't even know about them. What you eat will have more effect on you than most people. Eat regular meals, and stay healthy. Eat 2-3 hours before shooting. Bring a snack to the range. Wash hands before eating.