Being hungry and having an empty stomach can actually cause you to have low blood pressure.
Just like when someone is fasting they usually have a lower blood pressure reading than if they were eating.
Usually when you have a full stomach your blood pressure rises to normal levels but when you're hungry your blood pressure tends to low some.
When you get hungry and go without eating for awhile you become dizzy and weak and the dizziness is usually caused by lower blood pressure.
When I've been hungry and was fasting I started getting dizzy before and took my blood pressure reading and it was lower than normal.
When I started eating again my blood pressure reading returned to normal and I stopped feeling dizzy.