It is a myth, or very illogical, but there’s a saying that
you should have breakfast like a prince, lunch like a king, and dinner like a pauper.
I do not agree with this at all.
It depends from person to person whether you like to have lunch or dinner more, or less in quantity.
Again it depends on you, whether you like to have a big breakfast or a very small one.
How can anybody follow a thumb rule in this?
But yes you should never go to sleep immediately after a big meal, as it should be followed up with some activity of say one hour.
There’s another myth regarding water and it is said that one should always have huge quantities of water.
One should have water only as much as one likes to have.
No more, and no less.
Even birds and animals live with a lot less quantity of water than these myths or assumptions may suggest.