Answer: Her poor immune system is likely due to her deficiency of carbohydrates.
Explanation: Cheese sandwiches have hardly any carbs at all in them and that is her main source of food. She also barely eats fruits which are high in carbohydrates which may explain why her immune system has been poor. Carbs are known to play an important role in our immune system so her lack of carbs is likely the cause of the issue.