Heavy Meal and nightmares

If one eats a heavy meal, why is the sleep disturbed by nightmares?

Because there is a very close connection between dreams and the condition of the stomach. Observations have been made and it has been noticed that in accordance with what is eaten, dreams are of one kind or another, and that if the digestion is difficult, the dream always turns into a nightmare—those nightmares which have no reality but still are nightmares all the same and very unpleasant—seeing tigers, cats, etc…. Or else you experience things like… for instance, you are facing a great danger and must hurry up, get dressed quickly and go out, and then you can’t dress, try as you will, you can’t put on your things, you don’t find your things any more, and if you want to put on your shoes they never fit you, and if you want to go somewhere very fast, the legs don’t move any longer, they are paralysed and you are stuck there making formidable efforts to advance, and you can’t move. It is this kind of nightmare that comes from a disordered stomach.

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