How your job could ‘rapidly increase’ your risk of developing dementia – and we all do it

Research shows that spending more than 10 hours a day sitting increases your risk of dementia.

Scientists found that older adults who were largely inactive were more likely to suffer from the brain-robbing disease than those who exercised more.

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It didn’t matter whether the sitting periods took place in one long stretch or at certain points throughout the day – both had a similar effect.

Encouragingly, however, the results published in the journal JAMA showed that inactivity for less than 10 hours is not associated with an increased risk of developing the disease.

The researchers said it provided “some reassurance” for people with office jobs that require “prolonged sitting.”

Study author Gene Alexander, professor of psychology and psychiatry at the Evelyn F McKnight Brain Institute at the University of Arizona and the Arizona Alzheimer’s Disease Research Center in the US, said: “We were surprised to find that the risk of dementia begins to increase rapidly after this. “Spent 10 hours a day sitting, regardless of how the sedentary time was accumulated.

“This suggests that it is the total time spent sitting that determines the association between sedentary behavior and dementia risk. Importantly, however, lower levels of sedentary behavior, up to about 10 hours, were not associated with increased risk.”

In England, working-age adults spend an average of around 9.5 hours a day sitting.

This includes watching TV, using the computer, reading, doing homework and traveling by car, bus or train – but not sleeping.

According to the British Heart Foundation, average sedentary time among men and women aged 65 to 74 is increasing to 10 hours a day or more.

For the study, researchers examined data from more than 49,000 people aged 60 and over from the UK Biobank – an online database containing health and lifestyle data from half a million Britons.

These people did not have dementia at the start of the study and were followed for more than six years.

Participants were given devices to wear on their wrists to track their movements 24 hours a day for a week.

Using a type of artificial intelligence, so-called machine learning algorithms, the researchers classified types of movement and differentiated between, among other things, sleeping and sitting still.

During the course of the study, 414 people developed dementia.

When considering lifestyle factors that could impact brain health (such as diet, smoking, alcohol consumption and self-reported mental health) and demographic characteristics (such as age, gender, education level, ethnicity, chronic diseases and genetics), the team found that this is the case. Prolonged lack of exercise was associated with an increased risk of dementia.

Compared to adults who spent about nine hours a day sitting, those who sat for 10 hours were eight percent more likely to develop dementia.

And people who sat for 12 hours were 63 percent more likely to develop the disease.

Britain’s biggest killer

Study author David Raichlen, a professor of biological sciences and anthropology at the University of California Dornsife College of Letters, Arts and Sciences, said, “Many of us are familiar with the common advice to break up long periods of sitting by getting up every 30 minutes,” or so, to stand or walk around.

“We wanted to find out whether such patterns are associated with the risk of dementia.

“We found that when you take into account the total amount of time spent sitting, the length of each sitting period doesn’t matter much.”

Prof Raichlen said further research was needed to fully answer the question of whether physical activity could reduce risk after being sedentary for 10 or more hours.

He added: “The more cases of dementia that occur, the better we can answer this question.”

A previous study found that 30 minutes of exercise a day – such as an evening session at the gym – wasn’t enough to offset the health risks of sitting around for hours.

The University of Glasgow researchers instead encouraged people to get up and move every hour.

Meanwhile, another study published in the journal JAMA Network Open found that untreated high blood pressure is linked to a higher risk of dementia.

The researchers analyzed data from 14 different studies and surveyed more than 34,000 people aged 60 and over.

It found that people with untreated high blood pressure had a 42 percent increased risk of dementia compared to healthy people and a 26 percent increased risk compared to those who received treatment for the disease.

Dr. Richard Oakley, deputy director of research and innovation at the Alzheimer’s Society, said: “Dementia affects 900,000 people in the UK and is the leading cause of death in the country.”

“We know that some people are at greater risk than others due to factors such as age, genes and lifestyle.

“This study has shown that being inactive for more than 10 hours a day increases the risk of developing dementia later in life.

“As a rule of thumb, what’s good for the heart is also good for the head, and taking care of your cardiovascular health can reduce your risk of developing dementia in the future.

“A balanced diet, avoiding smoking and heavy alcohol consumption, and regular exercise can also help.”