Why does cataracts and depression affect use of sad lights?

Cataracts can impair vision and reduce the effectiveness of light therapy, as individuals may have difficulty seeing the bright light emitted by SAD lamps. Additionally, depression often leads to decreased motivation and energy, which can result in a lack of adherence to using these lights regularly. Together, these factors can diminish the potential benefits of light therapy in alleviating symptoms of Seasonal Affective Disorder (SAD).