From a Wall Street Journal online article:
Dementia is a complicated disease that has multiple causes and risk factors, some of which remain unknown. Nevertheless, there is increasing evidence that people—even those who inherit genes that put them at greater risk of developing Alzheimer’s in later life—can improve their chances by adopting lifestyle changes.
“It’s not just about running three times a week,” says Sarah Lenz Lock, executive director of AARP’s Global Council on Brain Health. “Instead, it’s about a package of behaviors, including aerobic exercise, strength training, a healthy diet, sleep and cognitive training.”
When it comes to battling dementia, the unfortunate news is this: Medications have proven ineffective at curing or stopping the disease and its most common form, Alzheimer’s disease. But that isn’t the end of the story. According to a recent wave of scientific studies, we have more control over our cognitive health than is commonly known. We just have to take certain steps—ideally, early and often—to live a healthier lifestyle.
In fact, according to a recent report commissioned by the Lancet, a medical journal, around 35% of dementia cases might be prevented if people do things including exercising and engaging in cognitively stimulating activities. “When people ask me how to prevent dementia, they often want a simple answer, such as vitamins, dietary supplements or the latest hyped idea,” says Eric Larson, a physician at Kaiser Permanente in Seattle and one of a group of scientists who helped prepare the report. “I tell them they can take many common-sense actions that promote health throughout life.”
To read more: https://www.wsj.com/articles/what-science-tells-us-about-preventing-dementia-11574004600
“This study identifies a new molecular connection between exercise and inflammation that takes place in the bone marrow and highlights a previously unappreciated role of leptin in exercise-mediated cardiovascular protection,” said Michelle Olive, program officer at the National Heart, Lung, and Blood Institute Division of Cardiovascular Sciences. “This work adds a new piece to the puzzle of how sedentary lifestyles affect cardiovascular health and underscores the importance of following physical-activity guidelines.”
The investigators discovered that patients with a higher genetic risk for depression were more likely to be diagnosed with depression over the next 2 years. However, more physically active patients at baseline were less likely to depression, even after they accounted for genetic risks.
“Another behavior change is physical exercise,” Pillemer said. “A paradox of pain is that exercise helps reduce it, but it’s difficult for people in pain to think about exercising. So they don’t exercise, they get more sedentary and the pain increases; it’s a vicious circle. So how do you get people to actually change their behavior?”
Researchers suggest that intensity is critical. Seniors who exercised using short, bursts of activity saw an improvement of up to 30 percent in 
Now 63, Mr. Peterson has progressed from bike paths to rugged mountain trails and is known for his caped helmet emblazoned with his nickname, UniGeezer. Based on his GPS and bike computer, he estimates he’s logged nearly 30,000 miles, or 24 million pedal revolutions, since he started.
“Living a healthy lifestyle may help offset a person’s genetic risk of dementia, according to new research.
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