READ THIS NEXT: Drinking This Popular Beverage Slashes Dementia Risk, New Study Says. Without a cure for dementia, research efforts are geared toward identifying how and why the disease occurs, and who is most at risk. Recently, investigators from the University of Cambridge in the U.K. and Fudan University in China found that middle-aged and older adults require seven hours of sleep each night to help stave off cognitive decline. When hours were below or above that number, study participants had poorer cognitive performance, affecting memory, processing speed, and the ability to solve problems. Getting the optimal number of hours is an easy lifestyle change to make now, but another recent study found that something you may have done earlier in life could also help mitigate dementia risk.ae0fcc31ae342fd3a1346ebb1f342fcb A study recently conducted in Japan found that having higher levels of education could reduce dementia risk. Findings were published this month in The Lancet, stating that by 2043, women and men over the age of 65 are also expected to see a decreased number of years spent with dementia, declining from 4.7 to 3.9 years in women and 2.2 to 1.4 years in men, as reported by Medical News Today. Findings were particularly prominent for men and are also attributed to reduced cardiovascular risks. “Our projection of reduced prevalence of dementia in the next 20 years in a subset of the population is good news for a rapidly aging but highly educated population, although this trend is unevenly distributed across the sexes and by socioeconomic status,” the study authors wrote, noting disparities between women and men in Japan, as educational and economic opportunities are less available to women, who also have greater levels of stress and poorer health. Interestingly, a 2013 Organization for Economic Co-operation and Development Adult Skills Survey found that when compared with college graduates in the U.S. and Europe, Japanese adults with high school diplomas had more work-relevant skills, study author Hideki Hashimoto, DPH, professor at the Department of Health and Social Behavior at the University of Tokyo, told Medical News Today. For more health advice delivered straight to your inbox, sign up for our daily newsletter.  Researchers developed a microsimulation using “nationally representative health surveys” and cohort studies to study how both dementia and frailty will change by 2043. As the population continues to age in Japan, which currently has the oldest population of any country, researchers work to address challenges and improve care for older adults. Rates of both frailty and dementia were found to be affected by age, gender, and education levels. as data showed that 29 percent of Japanese women over the age of 75 with less than high school education were anticipated to have dementia by 2043. When looking at frailty, only 6.5 percent of women over the age of 75 with a college education or higher were anticipated to be affected. Explaining lower dementia rates to Medical News Today, Hashimoto pointed directly to education levels, as 60 percent of men in Japan will be college graduates by 2035, compared with 43 percent of men between the ages of 55 and 64 who were college-educated as of 2016. While Hashimoto said the study could not definitively identify why or how these education levels affected dementia, it did reveal potential risk factors to address, as well disparities that should be better accounted for. Considering findings, experts and developers of public health policy may be able to better prepare and enact policies to “mitigate the health gap,” the researchers wrote. Scott Kaiser, MD, director of Geriatric Cognitive Health for the Pacific Neuroscience Institute, who was not affiliated with the study, spoke with Medical News Today on the findings, as well as the importance of recognizing modifiable risk factors. “Experts believe that something on the order of one out of three cases of dementia could be prevented through addressing 12 ‘modifiable risk factors’ for dementia,” Kaiser said. These include midlife obesity, physical inactivity, social isolation, and excessive drinking. “Likewise, along with population-level efforts to prevent dementia, a focus on early detection for earlier intervention could significantly mitigate the impact and extend healthy years. One of the greatest myths about Alzheimer’s disease (or other types of dementia) is that there’s “nothing we can do. [But] nothing could be further from the truth,” he added. READ THIS NEXT: Skipping This Step in the Bathroom Increases Your Dementia Risk.