Eating between meals disrupts digestion and ruins the appetite for wholesome food.

Original passage

Regularity in eating should be carefully observed. Nothing should be eaten between meals, no confectionery, nuts, fruits, or food of any kind. Irregularities in eating destroy the healthful tone of the digestive organs, to the detriment of health and cheerfulness. And when the children come to the table, they do not relish wholesome food; their appetites crave that which is hurtful for them.