From the perspective of geomantic omen, the kitchen is the energy area of fire, and there are many "dry fires"; Toilet is the energy area of water, so there are more "only yin qi", and water and fire are adjacent, which will cause magnetic field collision. Moreover, the bathroom door is easy to rush into the kitchen, which is also harmful to the health of family members.
From the health point of view, the kitchen is a place where a family cooks, while the bathroom is usually used for convenience and bathing, and it is often in a humid state, which is easy to breed bacteria and will affect the health of family members.
So the kitchen and bathroom are not close together. If it has been designed in this way, we can consider placing a screen or installing a door curtain between them to solve it.