According to Raise Smart Kid, excessive television consumption can contribute to several detrimental effects on children, including delayed cognitive development, obesity and behavioral problems. While it is difficult to tie direct links between television and any single consequence due to a large variety of factors, there are many secondary and tertiary effects that television can produce, particularly when used in excess.
Research has shown that children under the age of two form neurological connections best when interacting with objects and people in the real world, and simulated interactions using video technology are not as effective. If children spend too much time in front of televisions at an early age, their brains do not develop as quickly or as thoroughly as they would using proactive stimulation.
Children who spend significant time watching television or playing video games can suffer physiological consequences when they do not exercise as much as their peers. As a result, they are more likely to develop obesity, heart disease and high blood pressure.
Children are very susceptible to social influences, and the types of behaviors displayed on popular media can promote anti-social behavior. In fictionalized worlds of television and movies, children can develop skewed views of reality and believe that unprotected sex, drug use and violence carry little meaningful consequence.