The American Medical Association has adopted policy saying exposure to excessive light at night disrupts sleep and causes unsafe driving conditions. The AMA, the nation\'s largest physician organization, voted during its annual policy-making meeting in Chicago to support the need for developing lighting technologies that minimize circadian -- body clock -- disruption. The resolution encourages further research on the risks and benefits of occupational and environmental exposure to light at night. \"The natural 24-hour cycle of light and dark helps maintain alignment of circadian biological rhythms along with basic processes that help our bodies to function normally,\" Dr. Alexander Ding, an AMA board member, said in a statement. \"Excessive exposure to nighttime lighting disrupts these essential processes and can create potentially harmful health effects and hazardous situations.\" This type of disruption especially affects those employed by industries requiring a 24-hour workforce, as well those faced with unsafe driving conditions caused by artificial lights on cars and roadway illumination, Ding said.