A lack of exposure to sunlight can significantly affect health by leading to deficiencies in vitamin D, which plays a vital role in bone health and immune function. Insufficient sunlight can result in conditions like osteoporosis and increase vulnerability to infections. Moreover, inadequate sunlight exposure may contribute to mood disorders, including seasonal affective disorder (SAD). This is because natural light impacts the production of serotonin, a neurotransmitter that regulates mood. To mitigate these effects, individuals can seek alternative vitamin D sources, such as supplements or fortified foods, and aim for outdoor activities when possible.