night mares

Definitely is. The state of your sleep is important and is necessary for the body to recuperate during the night. If you have eaten a heavy meal just before going bed, when you fall asleep the body isn't resting, it's too busy digesting what you just ate. As such your consciousness is too embroiled in your physical body and is unable to go off into dreamland. Sleep is a non-physical state of consciousness. It is supposed to leave your body so the body can rest. Your consciousness goes off into all sorts of places and spaces during the night - you just don't remember. So if you are not in a good state when you are sleeping, you can experience nightmares or broken sleep and feel restless, and often wake up feeling like you've not been sleeping at all.

When you eat a heavy meal before bedtime, it is proven that it generally keeps you from having restful sleep, or sleep as restful as you would have otherwise, since you are busy digesting food. Sleeping lightly, I've found, tends to lead to dreams and/or nightmares, as my brain hasn't completely shut down for the rest. It might be better to snack lightly before bed if you find that you are having nighmares after a meal.

I don't know heavy meals after dinner will be having nightmares

Im not sure bout that.but i had nightmare several times even when i neve take my lunch.I don't know y nightmare happen to us.Wat is the reason of having nightmares..except having heavy meals.