Excessive TV watching and low levels of physical activity in young adults have been linked to lower cognitive function 25 years later, according to a research presented today at the Alzheimer’s Association International Conference in Washington.
More than 3,200 adults aged 18-30 years old in the Coronary Artery Risk Development in Young Adults (CARDIA) study were followed for 25 years. At intervals they were asked to report on physical activity and TV watching behaviour and at the end of the 25 years they were assessed for memory and processing speed using well established tests.
Participants who consistently reported low levels of physical activity (under 150 minutes of medium intensity exercise per week) or watching more than 4 hours of TV a day had significantly lower performance on the cognitive tests in middle age. Those who reported both low physical activity and high television viewing were almost two times more likely to have poor cognitive function at the end of the study.
Dr Doug Brown, Director of Research at Alzheimer’s Society, said:
‘We know that people who take regular physical exercise in mid and late life have lower rates of dementia than those who have a sedentary lifestyle. This study looks earlier, at people in their 20s and 30s, but it only measured cognitive performance once in mid-life so we cannot draw any conclusions about whether a sedentary lifestyle or excessive TV watching in young adults affects the risk of cognitive decline or dementia later on.
‘Alzheimer’s Society recommends that people keep as physically active as possible as well as eating a healthy diet, keeping alcohol intake within recommended limits and not smoking as ways to reduce the risk of developing dementia.’