Researchers through a recently conducted study have found that watching too much of TV can increase the risk of developing Alzheimer's disease.

Researchers at the Northern California Institute for Research and Education in San Francisco during their study investigated the association between sedentary lifestyles, cognitive performance and the risk of developing dementia.

Their exercise habits and TV viewing were evaluated using questionnaires three times during the course of 25 years. They found that people who often watched excess of television (four hours or more per day) scored significantly lower on measures of cognitive performance in middle age.

Researchers for the study tracked people for 25 years starting from the young adulthood. They found that people who also reported low levels of physical activity performed poor on cognitive tests.

Kristine Yaffe, a professor of psychiatry, neurology and epidemiology at the University of California in San Francisco, said in a statement that the study's findings have significant implications for children and young adults, who are usually seen busy with electronic gadgets with screens, which has become a part of a sedentary life at home and in the workplace.

Yaffe said an analysis of the results showed that people who watch a lot of television had a 1.5% higher risk of performing worse on cognitive tests compared with those who watched less television.

The study's findings appear as shifting demographics are rising the median age in the United States and several other developing countries.

According to the Alzheimer's Association, more than 28 million baby boomers are projected to develop Alzheimer's by 2050, and over 5 million people are presently battling with the disease.