Having cataract surgery can be a great way to reduce your risk of developing dementia. However, it is important to understand that the exact risk depends on several factors, including your age, gender, lifestyle, and the presence of other health conditions. Several studies have suggested that cataract surgery can lower the risk of developing Alzheimer's disease. The surgery involves the removal of the natural lens of the eye, which has a yellow tint, and replacing it with a clear artificial lens. In addition to lowering the risk of Alzheimer's, cataract surgery may also improve visual input to the brain by stimulating specialized retinal cells called intrinsically photosensitive retinal ganglion cells, which are sensitive to blue light and regulate circadian cycles. Besides improved vision, cataract surgery may also help improve social engagement, cognition, and general health. In particular, the procedure can increase drivers' nighttime vision. However, research on the link between cataract surgery and Alzheimer's disease is limited. A study by the University of Washington School of Medicine examined data from over 5,000 Kaiser Permanente Washington members ages 65 or older. The participants were followed until the onset of dementia and their cognitive abilities were tested every two years. The study found that cataract surgery reduced the risk of developing dementia by 30 percent. Furthermore, after accounting for factors such as age at diagnosis, gender, sex, and race, cataract surgery reduced the risk of developing Alzheimer's by an even greater degree. The study used a weighted marginal structural model that included the probability of surgery and other factors. The results were surprisingly strong. However, this effect may not be observed in all populations and researchers have no idea how subsequent cataract surgeries may affect the risk of dementia. Having cataract surgery is an excellent way to decrease your risk of dementia and may give you a few more years of quality life. It is not a cure for dementia but does offer several benefits including longer life, fewer hours spent at home, and more social interactions. In addition, cataract surgery may also increase the quality of light entering the eye which could improve brain health by stimulating specialized cells linked to cognition and sleep cycles. The University of Washington researchers tested the effects of cataract surgery on more than 3,000 people over three decades. Participants had cataract surgery, glaucoma surgery or both. A group of 3,038 people was tracked until they developed dementia and their cognitive abilities were evaluated every two years. The study's lead researcher Cecilia Lee said that the results were surprising but could be significant in helping to inform the development of new treatments for memory loss. The study found that participants who experienced a more noticeable vision improvement were more likely to perform better on tests of cognitive abilities but participants with glaucoma or cataracts had a higher rate of cognitive impairment than those without these conditions.