Presbyopia is a natural age-related change in vision that makes it harder to focus on near objects, such as reading or using a smartphone. It usually begins in your 40s and happens because the eye’s natural lens becomes less flexible over time. Common symptoms include needing brighter light to read, holding things farther away, and eye strain. Presbyopia can be corrected with glasses, contact lenses, or modern surgical options such as lens-based vision correction.