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  • At least 5.8 million people in the U.S. have Alzheimer’s disease.
  • There is no cure, but researchers are learning why taking certain actions can decrease the risk of developing the disease.
  • A new study found that certain healthy actions could mean living longer without Alzheimer’s disease.

Cases of Alzheimer’s disease continue to dramatically increase in the U.S.

According to the Centers for Disease Control and Prevention (CDC), at least 5.8 million people in the U.S. have the condition. The number of cases starts to rapidly rise with age. The number of people with Alzheimer’s disease (AD) doubles every year past age 65 – with symptoms showing up as early as age 60.

While there is no cure for Alzheimer’s disease, recent research has found that a healthy lifestyle can decrease the risk of developing the disease.

A study published today in the British Medical Journal (BMJ) found there are actions we can take that not only add years to our lives but add years lived without having Alzheimer’s disease.

For this study, researchers analyzed questionnaire-based data from 2449 men and women aged 65 years and older who participated in the Chicago Health and Aging Project (CHAP), a population-based cohort study designed to assess risk factors of AD in the general population.

Researchers developed a healthy lifestyle score based on five lifestyle factors, diet, cognitive activities, physical activity, smoking, and alcohol consumption.

To calculate life expectancy and years lived with and without AD, they developed a demographic tool combining the experience of people in varying states of health with total life expectancy and how long they could expect to live without AD.

Participants were evaluated for the condition every three years during the study period.

Study findings suggest that, on average, the total life expectancy at age 65 in people with four or five healthy factors was between 23 and 24 years, with only six to 10 percent spent living with AD.

For those with no, or one healthy factor, this was significantly shorter, and more of their life was spent living with AD.

“This investigation suggests that a prolonged life expectancy owing to a healthy lifestyle is not accompanied by an increased number of years living with Alzheimer’s dementia,” researchers concluded.

A healthy diet was determined using the Mediterranean-DASH Diet Intervention for Neurodegenerative Delay (MIND) diet score, which is strongly associated with slower cognitive decline and reduced risk of dementia.

“It is important to incorporate green leafy vegetables, whole grains, berries, fish, and nuts while cutting down on red meat to improve brain health,” Hayley B Kristinsson, PsyD, a neuropsychologist at UCI Health, told Healthline.

However, Kristinsson emphasized that reducing risk doesn’t necessarily mean preventing AD altogether.

“You can reduce your risk but still develop AD,” she said. “But you may develop it later in life or be less likely to develop it with certain lifestyle modifications.”

Late-life cognitive activity was measured by looking at how often participants engaged in seven mentally stimulating activities during the past year.

This included reading, visiting a museum, and playing mentally challenging games like cards, crosswords, or puzzles.

Kristinsson added that our education level might also influence AD risk.

“Increased risk of developing AD is associated with having fewer years of formal education,” she said. “And some researchers believe that education builds up’ cognitive reserve.’”

Kristinsson noted that, while mental exercise is important for maintaining good cognitive functioning throughout our lives, research is mixed regarding the effectiveness of brain games in actually preventing dementia.

“The key appears to be stimulating your brain to work in ways that it is not accustomed to,” she said. “Such as learning a new language or learning to play an instrument.”

Kristinsson believes this research is critically important.

“There have been many studies looking at increasing longevity, but few studies have looked at the quality of those extra years and whether they include increased time living with AD,” she said.

She cautioned that type of research is “challenging” because it’s observational and cannot establish causation.

“However, it helps further support the use of lifestyle interventions in the prevention and treatment of Alzheimer’s disease,” she said.

Researchers defined people who were healthy or at low risk as those who spent at least 150 min each week doing moderate or vigorous activity.

This included gardening or yard work, calisthenics or general exercise, bicycle riding, and swimming.

“The extra blood flow that exercise brings to the brain also has a detoxifying effect,” said Dr. Kellyann Niotis, a preventive neurologist at Weill Cornell Medicine. “It has been shown to aid in removing an abnormal toxic protein called amyloid that builds up in the brains of people with AD.”

She added that exercise also produces a chemical called brain-derived neurotrophic factor, which stimulates the development of new brain cells and helps protect older ones.

Although controversial, some studies find moderate alcohol use associated with reduced AD risk, possibly because it provides some cardiovascular health benefit.

Researchers analyzed this factor to discover moderate drinking was associated with reduced risk. However, they cautioned that people who don’t drink shouldn’t be encouraged to begin doing so.

“Following dietary guidelines for Americans 2020-25, those with light to moderate alcohol consumption (1-15 g/day in women and 1-30 g/day in men) were considered healthy or at low risk of Alzheimer’s dementia,” the study authors wrote.

Niotis said there are risk factors we can’t change; these include age, which is the highest risk factor, sex – with women experiencing AD more frequently, and genetics.

She added that other factors, some of which can be changed, also contribute to risk.

“For example, 12 factors including excessive alcohol consumption, traumatic brain injury, air pollution, less education, hypertension, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, and low social contact have been identified,” said Niotis.

Niotis said this study highlights that a woman’s brain ages differently. She added that some women might also be more susceptible to certain AD risk factors, such as the ApoE4 gene, which is the strongest risk factor for developing AD.

“Additionally, we are now elucidating the mechanism behind women’s AD risk as it relates to the ‘menopause transition’ period and the potential role of hormone replacement therapy on modulating risk,” she continued.

New research finds following a healthy lifestyle that includes exercise, a healthy diet, and keeping mentally active adds years to our lives and significantly delay the development of Alzheimer’s disease.

Experts say it’s particularly important to use our brains in new ways, such as learning a new language.

They also say this research supports lifestyle interventions to prevent or treat Alzheimer’s disease.