Answer:
Anorexia and Obesity.
Step-by-step explanation:
The answer is both extreme conditions, anoxeria and obesity.
Anorexia is caused when a person barely eats anyting to get the "perfect body model". This leads to a shortage of vitamins and many other important things. An anorexic person is very underweight.
The opposite of anorexia is the obesity, which happens when a child or a teen eats a lot, being very overweight.. It also leads to lots of health problems, especially cardiovascular.