On both sides at the back of the throat are the tonsils. The adenoids are found where the nasal passages meet the throat, higher and further back. The tonsils and adenoids play a part in the body’s ability to resist and fight infections. The tonsils are visible through the mouth, but not the adenoids. Enlargement is what hypertrophy refers to. In children, adenoid hypertrophy is frequent, but it is uncommon in adults. Chronic infection and allergies are the most prevalent causes of adenoid hypertrophy in adults. Pollution and smoking are also significant contributors to tonsil and adenoid enlargement.