Around 3.6 million Australians are affected by hearing loss – that’s one in six – and hearing loss is in fact the second most common medical condition, more common than cancer, heart disease, diabetes and asthma. It is on the increase (see below), with 25% of the population projected to be affected by 2050.

The biggest cause of hearing loss is exposure to loud noise over a period of time. This is largely preventable. Called noise-induced hearing loss, it is caused by damage to the inner ear (the ‘cochlea’ – more information on the cochlea here) by constant exposure to noise, which can be anything from noise in the workplace to common noise sources in daily life, such as cars, aircraft etc.

A major contributing factor to hearing loss, where we are unlikely to see the full impact until the current younger generation hit their 50s and 60s, is listening to music on personal devices such as iPods/smartphones through earbuds and headphones. Even going to nightclubs and live concerts has an impact on hearing and contributes to hearing loss.*

Although noise-induced hearing loss is the most common, there are other causes of hearing loss. These include:

• Middle ear infections
• Genetic/inherited hearing conditions
• Wax buildup in the ear or another form of blockage
• Head injuries/trauma
• Surgery in/on the head
• Some chemicals/medications (eg some chemotherapy drugs, some antibiotics and some erectile dysfunction drugs)
• Some conditions such as heart disease, diabetes and high blood pressure can restrict blood flow to the ears and affect hearing

(see also our section on ear diseases and infections)

Hearing also naturally declines with age (the medical term ‘presbycusis’ describes age-related hearing loss), with one in three people aged 65-74 affected, rising to one in two over the age of 75.

There are four types of hearing loss, and four grades of level of hearing loss.