While the link between poor sleep and dementia has long been known, it was unclear whether poor sleep habits could cause dementia or whether poor sleep was an early symptom of dementia. However, new research has revealed that sleep quality may have a direct impact on the rate at which the brain ages. Using these data, they categorized participants into three sleep patterns, finding that 41.2 percent had healthy sleep, 3.3 percent had clearly poor sleep, and 55.6 percent fell into the middle group. Poor Sleep Leads to Chronic Inflammation in the BodyTo understand the mechanism by which poor sleep affects the brain, the research team also measured the level of low-grade inflammation in the body. In other words, it is highly likely that poor sleep quality makes it easier for chronic inflammation to occur in the body, which in turn accelerates brain aging.