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Sit for more than 10 hours a day? You could be at a higher risk for developing dementia. ljubaphoto/Getty Images
  • A new study indicates that people who are sedentary for more than 10 hours a day may be at a greater risk of dementia.
  • Sedentary behavior can contribute to diseases like high blood pressure that put people at risk for dementia.
  • It might also create fewer opportunities for mental stimulation, which can contribute to cognitive decline.
  • Experts suggest seeking a doctor’s advice and starting slow as you increase your activity level.

New research reports that when older adults tend to be more sedentary, they are more likely to develop dementia.

This includes dementia due to any cause, according to the findings recently published in JAMA.

The Alzheimer’s Association explains that “dementia” is an umbrella term that refers to a collection of symptoms that are caused by abnormal changes in the brain. These symptoms can include a decline in a person’s ability to think and remember things that is severe enough to interfere with their daily life.

Their emotions, behaviors, and interpersonal relationships can also be impacted by the condition.

The organization further notes that Alzheimer’s disease is the most common form of dementia, accounting for 60% to 80% of all cases.

Vascular dementia is the second most common type.

The authors state in their report that half of Americans spend over 9.5 hours a day being sedentary.

Additionally, previous research has found sedentary behavior to be linked with cognitive and structural brain aging.

The purpose of the current study was to examine how being sedentary might affect the risk for dementia.

Sedentary behavior was defined for the purposes of the study as “any waking behavior characterized by an energy expenditure ≤1.5 METs [metabolic equivalent units] while in a sitting or reclining posture.”

Examples of sedentary behavior included watching television, using a computer, and driving.

To study how sedentary behavior influenced dementia risk, the researchers collected data from the UK Biobank, a large database of genetic and health information including about a half million people in the United Kingdom.

Nearly 50,000 people aged 60 and up who did not have a diagnosis of dementia at the outset of the study were included.

The study participants were asked to wear an accelerometer on their wrists for one week. A machine learning-based analysis was then performed on the data that was collected in order to assess how sedentary they were.

Individuals were then followed up for an average of 6.72 years to determine if they received a subsequent diagnosis of dementia.

When the data was analyzed, it was found that people who were sedentary for about 10 hours a day had a higher risk of dementia — a figure not far off from the national average of 9.5 hours, the researchers noted.

However, they caution that it is not possible to know, based on this study, whether being sedentary actually causes dementia. They suggest that more research is needed in order to determine the exact nature of the association.

According to Dr. Shara Cohen, founder and director of Cancer Care Parcel, there are multiple interconnected mechanisms through which sedentary behavior might contribute to an increased risk for dementia.

“Prolonged sitting reduces physical activity, which can lead to conditions like obesity, hypertension, and diabetes, all of which are known risk factors for dementia,” she explained.

“Additionally, physical inactivity may impair vascular health, reducing blood flow to the brain and increasing the likelihood of cerebrovascular disease.”

Cohen added that sedentary behavior is linked with lower cognitive stimulation and social engagement, which are both factors necessary for maintaining brain health.

“Overall, a sedentary lifestyle may contribute to the development of dementia by promoting various cardiovascular and neurodegenerative pathways while limiting cognitive and social engagement,” she concluded.

Dr. Kezia Joy, medical content advisor for Welzo, said that the amount of movement needed to reduce dementia risk can vary, depending on the individual. Generally, however, it is recommended that people get at least 150 minutes of moderate-intensity exercise each week.

“This can be broken down into 30 minutes a day for five days a week,” she suggested. “Alternatively, you can aim for 75 minutes of vigorous-intensity aerobic exercise per week, spread over at least three days.”

Joy further noted the importance of including strength training exercises for major muscle groups on two or more days per week.

“A well-rounded fitness routine that combines cardiovascular exercise, strength training, and flexibility can have the most significant impact on overall health and may help reduce the risk of dementia,” she said.

The first step in becoming more active, said Joy, is to consult with your healthcare provider, especially if you have any underlying conditions. “They can provide guidance and ensure that your chosen activities are safe for your specific situation.”

Joy further advised setting realistic, achievable goals that fit your current fitness level. From there, you can gradually increase your intensity, duration, and frequency as your fitness improves.

It is also important to choose activities that you enjoy since it will be easier to stick with your routine, she said. “Whether it’s walking, swimming, dancing, or playing a sport, find something you like doing.”

However, getting in more activity doesn’t necessarily have to come from a formal exercise program, according to Joy.

She suggests finding opportunities to move throughout your daily life. For example, if you work a desk job, you can take short breaks to stand, stretch, or walk around. You can also use the stairs instead of the elevator or walk or bike to work.

Joy further noted the importance of being consistent.

“Try to establish a regular exercise routine and make it a part of your daily or weekly schedule,” she advised.

As you start to move more, you should also take the time to listen to your body, she added. If you feel pain, discomfort, or anything out of the ordinary, stop and speak with your doctor if necessary.

Finally, said Joy, remember that the goal is to make physical activity enjoyable and sustainable.

“Gradual changes and small, consistent efforts can lead to improved overall health and a potential reduction in the risk of dementia,” she said.

A new study indicates that people who are sedentary for more than 10 hours a day may be at a greater risk of dementia.

Sedentary behavior can contribute to diseases like high blood pressure that put people at risk for dementia.

It might also create fewer opportunities for mental stimulation, which can contribute to cognitive decline.

Experts suggest seeking a doctor’s advice and starting slow as you increase your activity level.