Flopping infront of the TV – and similarly passive, sedentary behaviour – can increase the danger of dementia for over 60s. according to researchers at the Universities of Southern California and Arizona. And worryingly, this is true even if at other times you are physically active, they conclude. But the risk is lower for those who spend their ouch time on computers of reading, “It isn’t the time spent sitting, per se, but the type of sedentary activity performed during leisure time that impacts dementia risk,” said study author David Raichlen, professor of biological sciences and anthropology at the USC Dornsife College of Letters, Arts and Sciences. We know from past studies that watching TV involves low levels of muscle activity and energy use compared with using a computer or reading, And while research has shown that uninterrupted sitting for long periods is linked with reduced blood flow in the brain, the relatively greater intellectual stimulation that occurs during computer use may counteract the negative effects of sitting.”