Discipline should always take priority over Food..
Often mothers try to abide their children by rule, but she easily melts down when a child refuses to eat food.
Eg. A mother tries to limit TV viewing for one hour and switches off the TV. Children show reaction against it by throwing a tantrum or by refusing to eat anything. Now mother leaves her anger and switches on TV and asks her child to eat the Food.
This is a Mistake, Big Mistake. 
1. The mother loses her control on her child.
2. Children when they grow as an adult, behave similarly and can be easily manipulated by others.
A Mother should learn to say NO to her child as she only knows what is good or what is not good for her child.