Rickets, scurvy and "marasmus" may be instanced as diet diseases in children.
Marasmus usually develops between the ages of six months and one year in children who have been weaned from breast milk or who suffer from weakening conditions such as chronic diarrhea.
A form of severe malnutrition called marasmus retards growth in all parts of the body, including the head (causing mental retardation as well).
Marasmus can be caused by being weaned very early and not adequately fed afterwards; if the intake of calories and protein is limited severely enough, the body wastes away.
Marasmus, a PEM disorder, is caused by total calorie/energy depletion rather than primarily protein calorie/energy depletion.