Adults are recommended to have routine eye exams every 1-2 years because the eyes are an indicator of your overall health. Aside from determining the optimal glasses prescription for distance and reading based on your occupational and recreational needs, the optometrists will evaluate your eyes for common eye diseases and assess how your eyes work together. Optometrists can be the first to detect certain medical conditions that affect blood vessels (diabetes, high blood pressure, etc.) because the eyes are the only place in the body where blood vessels can be viewed directly. 

Adults aged 65 and older are recommended to have an eye exam every year because the prevalence of certain eye disease increase with age. Some common age-related eye conditions include cataracts, glaucoma and macular degeneration. Earlier diagnosis and treatment of eye disease could mean better visual outcome.