Alarm clockPoor sleep, especially in midlife, has been associated with an increased risk of developing dementia.We aren’t sure exactly why the two appear to be linked, though, and it can be very hard to unpick whether it’s an early symptom of Alzheimer’s vs an actual cause of it.New research, however, has found that turning off a circadian (related to the sleep-wake cycle) protein in mice reduced their levels of tau protein, the accumulation of which in the brain is linked to dementia. It also seemed to raise their nicotinamide adenine dinucleotide, or NAD+, levels, associated with increased