Scientists who study memory and other cognitive functions like to say that what’s good for the body is good for the brain, too, and proof for that axiom continues to grow.
A wealth of research shows that people who eat right, stay trim, and follow other well-established healthy habits have the best shot at remaining sharp-witted as they grow older.
Recently, several clinical trials have provided even more powerful evidence that adopting a healthy lifestyle can protect your brain and reduce the risk for age-related cognitive problems.
The FINGER Study
A number of population studies have found that people who engage in regular exercise, eat a healthful diet, and keep mentally active (with mentally challenging activities, for instance) have a reduced risk for cognitive decline.
But an association between a behavior and a health outcome doesn’t prove that one causes the other. For that level of evidence, scientists conduct clinical trials, randomly choosing one group of participants to receive a therapy or other intervention, then comparing their outcomes with other study participants who don’t receive the treatment being studied.
To determine whether healthy habits truly benefit the brain, a team of scientists in Finland set up an experiment called the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (abbreviated as FINGER), which they reported on in The Lancet in 2016.
The study included 1,260 men and women aged 60 to 77 who were generally healthy, though many had risk factors closely linked to dementia, including high blood pressure and high cholesterol, which may both be improved through diet changes and exercise.
At the outset of the study, all subjects had their memory and other cognitive skills tested, and only those whose scores were average or slightly below average were invited to participate.
Half of the FINGER subjects were enrolled in a comprehensive program of lifestyle changes. They were encouraged to eat a healthful diet that included plenty of fruit, vegetables, and whole grains, but avoid sugary treats and artery-clogging fats.
Men and women in the active treatment group were asked to follow fitness regimens that included both aerobic exercise (such as walking or jogging) and strength training. They were also required to use computer-based cognitive-training programs three times a week.
The other half of the subjects in the FINGER study were given basic health advice and served as a control (or comparison) group.
After two years, all FINGER participants took a second battery of cognitive tests. Men and women who adopted lifestyle changes showed a 25 percent improvement in memory and other thinking abilities compared to subjects in the control group.
According to the authors, the FINGER study is the first long-term clinical trial to show that lifestyle changes can help prevent cognitive decline.
Obesity and other risk factors
In another 2016 study, published in the Journal of Clinical Endocrinology and Metabolism, Brazilian researchers focused specifically on the role of obesity, which studies have linked to an increased risk for dementia.
The authors of this study recruited 80 obese people aged 60 and older who had been diagnosed with mild cognitive impairment, which is a subtle, but noticeable age-related decline in thinking ability, and another known risk factor for dementia. Could shedding some pounds help protect these men and women from memory loss and other cognitive woes?
To find out, the researchers randomly chose half of the participants to receive weight-loss advice from a nutrition counselor. After one year, participants who lost even a modest amount of weight showed improvements in their overall cognitive capacities, ability to recall words, language skills, and executive function (or ability to focus attention and multi-task).
In addition to eating well and staying fit, keeping your brain busy may help stave off the loss of mental acuity, too, according to some studies, though most were small and the benefits of cognitive training remain controversial. On the other hand, one recent trial found evidence that seniors who become socially engaged may improve brain health.
As part of the ongoing Brain Health Study, researchers from the Bloomberg School of Public Health at Johns Hopkins performed magnetic resonance imaging (MRI) scans on the brains of 111 men and women aged 60 and older from the Baltimore area.
Next, about half of the subjects were assigned to work as volunteer tutors and teachers’ aides in inner city kindergartens and elementary schools. The remaining men and women acted as a control group.
Two years later, a follow-up set of MRIs showed that men and women in the control group had experienced slight shrinking in several brain regions, including the hippocampus; loss of volume in the hippocampus has been linked to memory problems and an increased risk for Alzheimer’s disease. Meanwhile, men and (to a lesser extent) women volunteers who worked in schools showed increased volume in this important brain region.
What you can do
There’s plenty of proof that the same steps that reduce the risk for common diseases can also help keep your mind sound and functioning at a high level.
A major 2015 review by the Alzheimer’s Association found convincing evidence that you can reduce the risk for age-related cognitive decline, and possibly dementia, by exercising regularly and taking steps to curb cardiovascular risk factors. That means watching your weight, avoiding or managing diabetes and high blood pressure, and not smoking.
Consuming a healthful diet and staying mentally engaged through learning may help, too.
There’s really no downside to adopting these good habits, so the only question that remains is: What are you waiting for?
Read more about how diet may help reduce your risk of Alzheimer's.