The evidence is mounting that healthy lifestyle changes—exercising roughly 2.5 hours per week, eating a plant-based, low-carb diet, limiting drinking, quitting smoking, and engaging in mentally stimulating activities like crosswords—can help keep Alzheimer’s at bay.
In new work being presented today at the Alzheimer’s Association International Conference in Los Angeles, CA, researchers from Rush University in Illinois found that these five changes were associated with slightly lower dementia rates across two study groups. The only catch? They only worked if individuals went all in with several of them.
Nearly 3,000 older adults participated in the study, which has not yet been published in a peer-reviewed journal. They came from two groups, the Chicago Health and Aging Project and the Rush Memory and Aging Project. In the first group, participants followed up with their doctors every three years; the second had annual checkups. For the duration of the study, they tried to adhere to these five habits. During office visits, they reported to their doctors how many healthy habits they stuck to. Doctors also kept track of whether or not participants were diagnosed with Alzheimer’s disease.
Participants stayed in the study for a median length of six years. The patients who stuck with more healthy habits were less likely to develop Alzheimer’s. In total, 626 individuals were diagnosed with Alzheimer’s during the study. Among those who followed none or only one of the healthy habits, roughly one person out of every 100 developed Alzheimer’s. Among those who adopted four or five lifestyle changes, that rate was only one in 300.
The cumulative effect of their benefits likely stems from the fact that each of these changes is effective in the same way, according to Klodian Dhana, a geriatrician at Rush University who presented the research.“I like to think of it as a balance,” says Nilufer Ertekin-Taner, a neurogeneticist at the Mayo Clinic in Jacksonville, Florida who was not affiliated with the work. On one side of the scale are risk factors for dementia, and on the other there are protective factors against it. While adopting one lifestyle change may not be enough to tip the scale towards protection, several can do the job at once.
Because this was an observational study, it’s not clear if certain lifestyle changes were more or less beneficial than others—or how. One theory is that they bolster heart health. All of the changes, except for participating in cognitively stimulating games, help the cardiovascular system, and heart disease is a known risk factor for dementia.
Adhering to a healthy lifestyle certainly can’t guarantee that you won’t develop dementia. There are genetic risk factors for Alzheimer’s disease, too. Outside of three single mutations that always lead to Alzheimer’s (which make up only about 1% of total cases), scientists still aren’t sure how these genetic mutations put a person at higher risk of developing the disease.
Yet even in these cases, adopting a healthier lifestyle may help. Separate research published in the journal JAMA today suggests that even those at a high risk of developing dementia based on their genes may be able to lower that risk if they also adopt healthy lifestyle changes.
In the face of disappointing results from decades of research into potential treatments, it’s comforting to know that something could work to reduce the chances of developing Alzheimer’s. Earlier this year, the World Health Organization issued guidelines that echoed the benefits of healthy living for dementia prevention, in the wake of dozens of failed clinical trials. Just this week, drug giants Novartis and Amgen abruptly ended a late-stage clinical trial for a drug that blocks the formation of a protein that leads to amyloid-beta, one of the signatures of the disease.
Not that researchers will stop pursuing pharmaceutical treatments for Alzheimer’s disease. Realistically, some older adults may face barriers to adopting these lifestyle changes, like confounding health problems that limit their diet or mobility. Lifestyle changes could hold the key for these future therapeutics, says Henriette van Praag, a neuroscientist at Florida Atlantic University who was also unaffiliated with the work. If researchers can harness the physiological benefits of some of these lifestyle changes, perhaps those can become the targets of future drug developments themselves.