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Chronic constipation can be due to diet
poor in roughage or fiber, dehydration, diabetes
, hypothyroidism, colon disorders, irritable bowel syndrome, diverticular diseases, cancers, severe acidity etc. It can also be due to milk allergy and other food allergies. A proper investigation is required preferably by a gastroenterologist (a doctor who looks after the digestive system) to know what is the cause. The treatment will follow correct diagnosis.