Set aside that crossword puzzle and get moving, because exercise is one of the best things you can do for an aging brain. Numerous studies have found a strong association between physical activity and a reduced risk of cognitive decline. Work at Massachusetts General Hospital revealed that engaging in physical activity also helped slow the loss of brain tissue. The mechanisms are unclear, but study authors speculate that in addition to increased blood flow to the brain, the effect may be influenced by reduced inflammation, increased levels of an exercise-induced hormone called irisin, and other types of beneficial cellular activity. The study, published last year in the journal JAMA Neurology, involved having 182 older adults, some with elevated levels of brain amyloid and higher risk of cognitive decline, wear pedometers. Researchers saw the most prominent brain-preserving effects at 8,900 steps.
2. Eat a Healthy Diet
Diets high in plant-based foods and low in meat and saturated fats, such as the Mediterranean or the DASH (Dietary Approaches to Stop Hypertension) diets, have been shown to lower blood pressure and reduce the risk of heart disease. They also are known to substantially slow age-related cognitive decline in healthy older adults. A combination diet developed in 2015 at Rush University Medical Center in Chicago called MIND, for Mediterranean-DASH Intervention for Neurodegenerative Delay, builds on these and includes specific recommendations of what to eat — and what not to eat — for cognitive health. It calls for having at least three servings of whole grains, a leafy green vegetable, and one other vegetable every day (along with a glass of wine); snacking regularly on nuts; eating beans every other day or so, poultry and berries at least twice a week, and fish at least once a week. Go light on butter and limit cheese, sweets, and fried or fast food. A phase-three randomized-controlled trial is testing the effects of the diet on the cognition of overweight adults age 60 and older with suboptimal diets; results are expected in 2021.
3. Get Plenty of Sleep
Sleep is essential for both cognition and brain function, and poor sleep quality can be correlated with the development of Alzheimer’s disease. A 2019 study led by Laura Lewis, an assistant professor in biomedical engineering at Boston University, built on earlier research showing that animal brains cleared out more amyloid while sleeping than while awake. Her group’s study on humans showed how this likely happens. When the researchers used MRI and other imaging techniques to observe the brains of sleeping women and men, they noticed that the cerebrospinal fluid, which effectively rinses the brain of waste products like amyloid, started to pulse in large, slow waves. They also recorded a corresponding change in blood oxygenation that would allow the fluid to circulate. The researchers didn’t measure toxin levels, but “it seems that the large, pulsating waves of fluid we observed would increase that beneficial circulation, mixing, and waste-clearing,” Lewis says. Whether you aim for seven, eight, or nine hours a night, getting adequate, brain-cleansing sleep won’t just help you feel less groggy in the morning, it may also keep you bright and alert in the years to come.
4. Take Care of Your Heart
“Every research study to date has shown that what is good for your heart is also good for your brain,” says Dr. Jeff D. Williamson, chief of gerontology and geriatric medicine at Wake Forest School of Medicine in North Carolina. He leads a large, randomized-controlled trial called SPRINT (Systolic Blood Pressure Intervention Trial) MIND (Memory and Cognition in Decreased Hypertension). Last year showed that when older adults with certain levels of high blood pressure receive treatment, it can help reduce the development of mild cognitive impairment. Now, a follow-up study, SPRINT MIND 2, is looking at whether intensive blood pressure treatment can reduce the risk of developing more advanced dementia. Other research will gauge whether lowering cholesterol can reduce early and late dementia risk. Williamson says the patients he sees fear losing cognitive functions more than they do dying, and the good news is “there is something we can definitely do about this.” A number of somethings, really: Help boost heart and vascular health by exercising more, eating better, quitting smoking (a significant risk factor for Alzheimer’s), limiting alcohol, and making sure your blood pressure is in a healthy range.
5. Stay Socially Connected
Social engagement seems to be linked to better brain fitness, although researchers have yet to prove this definitively. What we do know is that having connections to others helps decrease stress, which in turn is linked to neurodegeneration. A rich social network can also be a strong motivator to stay active, healthy, and engaged with life. Keep in touch with family and friends, get involved with your local community, seek out group exercise classes or fitness clubs, and invite friends to join you on walks. When practicing social distancing, befriend technology, and fill your calendar with phone calls and video chats.
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