As dementia rates continue to rise and many people fear for their own brain health and that of older relatives, interest has grown in finding relatively simple ways to help ward off disease. Professors in the Robert Stempel College of Public Health & Social Work have investigated the relationship of sleep, diet and stress to Alzheimer's. Out of their work come suggestions of potential value to anyone concerned about preventing illness and improving their overall wellbeing.
Poor sleep and sleep deprivation negatively affect the makeup of your gut microbiome, which can lead to a more inflammatory gut microbiome. An unhealthy gut can result in failure to produce the compounds needed for proper brain function.
The resulting inflammation and impaired brain function open the door for toxic proteins to accumulate, raising the risk of Alzheimer's disease.
The good news: There are everyday things you can do to try to prevent this unhealthy cycle. Here are five tips – small but impactful habits – to strive for that might make a meaningful difference in your senior years.
1. Snooze Smart
Aim for 7-8 hours of solid sleep – your brain cleans up while you power down.
Sleep problems are modifiable risk factors for Alzheimer's disease. Sleep problems impact one-third of U.S. adults – that's 83.6 million Americans who sleep less than the minimum recommended 7 hours per night. In Florida, 37% of adults report that they do not get adequate sleep. That number rises to 38% in Miami-Dade and 41% in Broward counties.
Our studies have found that sleep efficiency (the time you are asleep compared to the total time in bed) is significantly associated with executive attention after adjusting for education and income. Executive attention helps you stay focused, ignore distractions, switch tasks when needed, and stay in control when you're feeling overwhelmed or pulled in many directions. Put another way, inadequate sleep negatively affects our ability to focus on these higher-level tasks.
Sleep fragmentation (waking up after you were asleep) was significantly associated with immediate memory. In our studies, this meant that people who had more frequent interruptions of their sleep had poorer performance on cognitive tests of immediate memory, or the ability to repeat information after they have heard it.
2. Stress Less, Think More
Chronic stress shrinks brain power.
One key to decreasing future negative cognitive outcomes might be related to controlling our anxiety. Our previous studies have shown a relationship between anxiety and future Alzheimer's disease risk.
Cortisol is a hormone your body releases when you're stressed. It can help with energy, alertness, and dealing with inflammation. But when stress is chronic, cortisol levels can stay high for too long – and that's not healthy.
In our studies, we measure cortisol through saliva. We found that how well people slept affected the link between their morning cortisol levels and how well they remembered things later. The interaction between sleep duration and cortisol at bedtime was significantly associated with nonverbal memory – the ability to recall things such as images, shapes, faces, and emotional content. In other words, better sleep quality is associated with lower morning cortisol levels, which is associated with better nonverbal memory.
Meet the authors
Shanna Burke is an associate professor of social work. Her research focuses on cognition and cognitive impairment, including neurodegenerative disorders, such as Alzheimer's disease, and works to identify midlife risk factors for late-life neurodegeneration and interventions targeting cognitive impairments and chronic diseases across the lifespan.
Sabrina Sales Martinez is an associate professor of dietetics and nutrition. She investigates how modifiable and cardiometabolic risk factors in populations living in South Florida may affect the intestinal microbiome, risks for chronic conditions and health outcomes.
