We all have nights where we toss and turn, struggling to fall asleep. It’s known that Alzheimer’s disease itself leads to disruptive sleep patterns, and also that quality of sleep can either positively or negatively influence brain health. But new research suggests that even one night of poor sleep can affect your Alzheimer’s risk.

Otherwise healthy adults who couldn’t reach the deepest stages of sleep displayed a buildup of Alzheimer’s related proteins in their cerebral spinal fluid, according to the study.

The 17 participants, who were between the ages of 35 and 65, had no sleep disorders and considered themselves healthy, had their sleep tracked both at home and in a lab. The research team, led by neurologist David Holtzmann of Washington University School of Medicine in St. Louis, interrupted participants’ sleep by sending intermittent beeps through headphones. The noises prevented them from falling into deep sleep. They were enough to disturb them, but not enough to wake them completely.

In just one night, poor sleep led to an increase of beta-amyloid in the brain, according to the findings. After one week of disruptive sleep, an increase in tau, another protein associated with Alzheimer’s, was apparent.

In short, the more deep sleep that was missed, the more toxic protein levels were present in the morning.

Previous findings have linked poor sleep quality to an increased risk of Alzheimer’s, and this study supports that. It also portrays the urgency of getting deep sleep, as it directly impacts your cognitive health.

Still, it’s not entirely clear which comes first in this chicken or the egg scenario. Does Alzheimer’s cause poor sleep, or does poor sleep contribute to the development of Alzheimer’s?

In any case, this new study provides a bit more insight into the relationship between sleep and Alzheimer’s, and stresses the importance of early intervention.