What is the function of the Eustachian tube?

The function of the Eustachian tube focuses on its role in connecting the middle ear to the nose and pharynx. This connection is essential for equalizing pressure between the middle ear and the external environment, which helps maintain proper eardrum function. When the Eustachian tube opens, air can flow in or out of the middle ear, allowing pressure changes, such as those experienced during altitude changes or when swallowing, to be balanced. This pressure equalization is vital for good hearing and preventing discomfort or potential damage to the ear.

In contrast, regulating hormone levels is related to endocrine functions and not relevant to the structure or purpose of the Eustachian tube. Facilitating balance is primarily a function of the inner ear's vestibular system, rather than the Eustachian tube. Although protecting the ear from infections can be partly influenced by the Eustachian tube, its primary role is more about pressure regulation and ventilation of the middle ear.