There is no proven method to prevent late-life dementia, according to a study published this month by the University of Minnesota’s School of Public Health.

University researchers reviewed more than 1,000 studies and determined that too many complicating factors exist to confidently point to any one preventative measure based on available research. Experts say focusing on living an overall healthy lifestyle is the best method to reduce the chances of developing dementia. 

“There really is no magic bullet in preventing cognitive decline,” said co-lead researcher and University assistant professor Dr. Mary Butler.

Dementia — a broad term describing cognitive decline severe enough to affect daily life with symptoms including impairment of memory and communication skills — is caused by damage to brain cells. Alzheimer’s disease is the most common type of dementia.

More than 5 million Americans are currently living with Alzheimer’s, and by 2050, experts predict as many as 16 million people could have the disease.

Common types of interventions studied by researchers include cognitive training, medication, vitamins, healthy diet, exercise and physical activity.

Researchers use two study types to monitor cognitive function: randomized control trials and epidemiological trials, said long term care professor in nursing Dr. Joseph Gaugler.

Randomized control trials — in which participants are randomly assigned to either receive the treatment or a placebo — often produce the most accurate evidence because outside factors may not influence results. Epidemiological trials are conducted over extensive time periods, which is beneficial for dementia studies because proving an intervention’s effectiveness may take a long time, Gaugler said. 

“Cognitive decline is very hard to study and modify because it often requires fairly long-term follow-up,” Gaugler said, adding that sometimes even three years isn’t enough time to gather adequate data. 

Examining results from both study types provides a more comprehensive view of findings in dementia trials, but extraneous factors are unavoidable, Gaugler said.

“These studies and these study types offer one answer to one piece of a much larger, complicated puzzle because it is a puzzle that lasts for a long time,” he said.

Though there may not be a proven method to prevent late-life dementia, people should continue live a balanced lifestyle and do activities that make them happy, even if they’re diagnosed with a form of the disease, said program and education manager at the Alzheimer’s Association Katie Roberg. 

The most effective intervention to prevent cognitive decline is most likely a combination of physical exercise, healthy diet and cognitive stimulation, Butler said. However, even the strongest evidence is still relatively weak, she said. 

“Food can taste good. Being cognitively engaged can really mean having fun, and being physically active can feel good,” she said. “These are not actually bad things to ask people to do. They are actually how we experience life, so go do them and enjoy it.”