Exercising Reduces Risk of Dementia - But Not If There's Air Pollution (irishtimes.com) 38
Two new studies involving tens of thousands of British men and women "found that, most of the time, people who ran and rode vigorously had larger brain volumes and lower risks for dementia than their less active peers," reports the New York Times. (Alternate URL here.)
"But if people exercised in areas with even moderate levels of air pollution, the expected brain improvements from exercise almost disappeared...." [F]or the first of the new studies, published in January in Neurology, researchers at the University of Arizona and University of Southern California pulled records for 8,600 middle-aged adults enrolled in the UK Biobank. A huge trove of health and lifestyle records, the Biobank holds information on about more than 500,000 British adults, such as their ages, home locations, socioeconomic status, genomes and extensive health data. Some of the participants also completed brain scans and wore activity monitors for a week to track their exercise habits.
The researchers focused on those who had worn a monitor, had a brain scan and, according to their trackers, often exercised vigorously, such as by running, which meant they breathed heavily during workouts. The heavier you breathe, the more air pollutants you draw in. The researchers also included some people who never worked out vigorously, for comparison. Using established air quality models, they then estimated air pollution levels where the people lived and, finally, compared everyone's brain scans.
As expected, vigorous exercise was linked, in general, to sturdy brain health. Men and women who lived and presumably worked out in areas with little air pollution showed relatively large amounts of gray matter and low incidence of white matter lesions, compared to people who never exercised hard. And the more they exercised, the better their brains tended to look. But any beneficial associations almost disappeared when exercisers lived in areas with even moderate air pollution. (Levels in this study were mostly within the bounds considered acceptable for health by European and American air quality standards.) Their gray matter volume was smaller and white matter lesions more numerous than among people living and exercising away from pollution, even if their workouts were similar.
Extending these findings in a second, follow-up study published this month in Medicine & Science in Sports & Exercise, the same scientists repeated aspects of this experiment with another 35,562 older UK Biobank participants, comparing people's exercise habits, local pollution levels and diagnoses of dementia, if any. The data showed the more people exercised, the less likely they were to develop dementia over time — provided their local air was clear. When it was moderately polluted, though, they had an increased long-term risk of dementia, whether they exercised or not.
The Times also got this assessment of the studies from pollution researcher Pamela Lein, a professor of neurotoxicity at the University of California, Davis.
"The observation that air pollution negates the well-established beneficial effects of exercise on brain health is alarming and increases the urgency for developing more-effective regulatory policies" related to air quality.
"But if people exercised in areas with even moderate levels of air pollution, the expected brain improvements from exercise almost disappeared...." [F]or the first of the new studies, published in January in Neurology, researchers at the University of Arizona and University of Southern California pulled records for 8,600 middle-aged adults enrolled in the UK Biobank. A huge trove of health and lifestyle records, the Biobank holds information on about more than 500,000 British adults, such as their ages, home locations, socioeconomic status, genomes and extensive health data. Some of the participants also completed brain scans and wore activity monitors for a week to track their exercise habits.
The researchers focused on those who had worn a monitor, had a brain scan and, according to their trackers, often exercised vigorously, such as by running, which meant they breathed heavily during workouts. The heavier you breathe, the more air pollutants you draw in. The researchers also included some people who never worked out vigorously, for comparison. Using established air quality models, they then estimated air pollution levels where the people lived and, finally, compared everyone's brain scans.
As expected, vigorous exercise was linked, in general, to sturdy brain health. Men and women who lived and presumably worked out in areas with little air pollution showed relatively large amounts of gray matter and low incidence of white matter lesions, compared to people who never exercised hard. And the more they exercised, the better their brains tended to look. But any beneficial associations almost disappeared when exercisers lived in areas with even moderate air pollution. (Levels in this study were mostly within the bounds considered acceptable for health by European and American air quality standards.) Their gray matter volume was smaller and white matter lesions more numerous than among people living and exercising away from pollution, even if their workouts were similar.
Extending these findings in a second, follow-up study published this month in Medicine & Science in Sports & Exercise, the same scientists repeated aspects of this experiment with another 35,562 older UK Biobank participants, comparing people's exercise habits, local pollution levels and diagnoses of dementia, if any. The data showed the more people exercised, the less likely they were to develop dementia over time — provided their local air was clear. When it was moderately polluted, though, they had an increased long-term risk of dementia, whether they exercised or not.
The Times also got this assessment of the studies from pollution researcher Pamela Lein, a professor of neurotoxicity at the University of California, Davis.
"The observation that air pollution negates the well-established beneficial effects of exercise on brain health is alarming and increases the urgency for developing more-effective regulatory policies" related to air quality.
Duh. Nice confirmation though. (Score:2)
I live near a four lane boulevard with wide sidewalks on both sides and pedestrian bridges that provide for runs that don't cross intersections up to 6 miles. However, unless I run in the very early morning when there is virtually no traffic, my performance measurably drops and I get side cramps. If a really smelly vehicle passes (I live in a state with no inspections so there are many), the effect is quick. I don't have experiences like that when I run out in the countryside or even in a neighborhood away
Re: Duh. Nice confirmation though. (Score:1)
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Perhaps you should consider taking Trump's dick out of your mouth.
Association (Score:2)
It's a correlation study. It's in the title of the paper "Association of Air Pollution and Physical Activity With Brain Volumes"
For the second time in a week, the slashdot editors have allowed a statistical association correctly described in the paper to be presented as causation in the title. Incompetence abounds.
This study does not show that exercise causes brain health. It shows that brain volume correlates with exercise in the presence clean air.
Maybe having a healthy brain and clean air gets you in the
Re: Association (Score:2)
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We really need to rethink urban planning to reduce our exposure.
Long before we could move cities to new layouts, EVs will eliminate this issue.
Re: Association (Score:2)
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>Tyres and asphalt still generate some particulates.
And also brake pads, and older catalytic converters. When you add up all the materials worn down into micro particles that can easily be breathed down deeply into the lungs, their negative effects go largely unmeasured.
"Some particles may be more equal than others" https://www.newscientist.com/l... [newscientist.com]
"Auto emissions are a key factor in the creation of tiny matter called ultrafine particles and pose a significant health problem in many urban areas" https:// [futurity.org]
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We really need to rethink urban planning to reduce our exposure.
Long before we could move cities to new layouts, EVs will eliminate this issue.
I'm on my second EV. I guess I'll live forever.
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It's a correlation study. It's in the title of the paper "Association of Air Pollution and Physical Activity With Brain Volumes"
For the second time in a week, the slashdot editors have allowed a statistical association correctly described in the paper to be presented as causation in the title. Incompetence abounds.
You seem to think that researchers have never heard of "correlation does not imply causation". In general, they are very aware of this and do their best to control for it (though it's never possible to do so perfectly).
This study does not show that exercise causes brain health. It shows that brain volume correlates with exercise in the presence clean air.
Maybe having a healthy brain and clean air gets you in the mood to exercise. This study is not designed to distinguish the direction of causation.
So if your alternate explanation is that "healthy brain + clean air = exercise" then how do you explain the fact that people exercised without clean air?
Just like the other poster who blamed the difference on city stress (yes somehow, only the stressful people in the city exercise?).
There's a
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Just like the other poster who blamed the difference on city stress (yes somehow, only the stressful people in the city exercise?).
Exercise is broadly recommended as a way of reducing stress, so although that is unlikely to be the primary reason for these differences, it could easily be a contributing factor.
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>You seem to think that researchers have never heard of "correlation does not imply causation". In general, they are very aware of this and do their best to control for it (though it's never possible to do so perfectly).
I don't think that at all. The researchers did fine. The git that wrote the headline did not.
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For the second time in a week, the slashdot editors have allowed a statistical association correctly described in the paper to be presented as causation in the title. Incompetence abounds. This study does not show that exercise causes brain health. It shows that brain volume correlates with exercise in the presence clean air.
Maybe having a healthy brain and clean air gets you in the mood to exercise.
The study involved a comparison between people with similar levels of exercise, so at least superficially, that doesn't sound like a plausible interpretation of the data to me.
This study is not designed to distinguish the direction of causation.
I think we can also safely rule out the possibility that having a healthy brain and higher levels of exercise results in cleaner air.
This leaves only two likely possibilities:
How did they factor in stress levels? (Score:2)
A London lawyer who jogs is likely going to have a lot more stress than an elementary school teacher in a rural area.
It is an interesting story, but you're comparing 2 sets of organisms with dozens of variables,
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While my urban area is extremely safe, having lived in a bad neighborhood when I was younger, I still am very aware of my surroundings, sudden movements, people looking at me, etc.
On the other hand, you'll never see or hear that cougar sneaking up on you in a rural area.
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While my urban area is extremely safe, having lived in a bad neighborhood when I was younger, I still am very aware of my surroundings, sudden movements, people looking at me, etc.
On the other hand, you'll never see or hear that cougar sneaking up on you in a rural area.
Just stay out of the bars and you'll be fine.
Answer: City Life is more Darwinistic (Score:2)
Every fit city person I know has a good or stressful job. Every fitness freak I know in the deep burbs or rural areas is usually less career-focused.
Why are these two items mutually exclusive? Personal anecdote: I live in a rural area with gigabit fiber internet and a fairly good job. One of the perks of said fairly good job is being able to work remotely. I'm at the gym every day for at least an hour doing moderate to heavy exercise. I'm not sure if this qualifies as a "fitness freak" or not, but suffice to say, there's one example that falls outside your data set.
Fitness is a mid-level need on Malsov's Hierarchy of needs. Most people don't care about cardio vascular health if they can't pay their bills or are drowning in responsibilities, like new parents. Living in a polluted urban area is another stressor. If you're in the nice part of town, you HAVE to work hard in order to earn enough money to raise a family there...and be comfortable enough to exercise. If you're in the shitty part of town, your life is probably not stress-free enough that you can worry ab
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If the test has enough members, stress will be randomly distributed. They ought to have verified this, as the test is invalid otherwise. IIRC from university, the routine is supposedly a T Test followed by an ANOVA followed by a chi-square.
Cause of Dementia (Score:1)
By far the largest cause of dementia in the US and Europe is the 4 years that Trump spent in office. Fully at least one half of voters developed a severe case, even the ones who exercised, but especially the ones who smoked dope.
This is a correlation (Score:1)
As I've noted many times, only prediction is valid in science. (And, yes, I do expect it to turn out to be true, and have held air pollution damages the brain for many years, based on predictive science carried out in the 1970s on specific forms of air pollution.)
So if this research can be used to form a predictive model which is then tested and not falsified, we can be assured that the relationship is indeed one that can be generalised.
But this research, in itself, tells us nothing because it neither indic
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Let's take the Big Bang. We know that the model predicts certain particles to exist under specific conditions in the quark-gluon soup that would result from the Big Bang. We know that these particles exist when we recreate those conditions in particle accelerators, thus confirming that the model is producing accurate predictions, so we know that the model accurately describes the physics.
Once neutrino telescopes and gravitational telescopes can peer into the time prior to the CMBR, we can verify the predict
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You're being a little too narrow in your definitions, I think.
The purpose of a control group is to be able to compare the group you're examining against the norm in order to determine if there is a signal present, that you're not just wanting to see one and that it is not a product of variables you are not looking at (because those are wholly randomised).
We can compare the region of space that we think has a black hole with how space behaves without anything present, with how space behaves when any other id
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good thing my city apt has air filters (Score:1)
Particle size matters or not? (Score:2)
Pollution isn't uniform. One difference between air pollution sources is particle size. Diesel engines produce large particles, which some people think aren't as dangerous as lots of small particles. But because they're so big, one typical way to measure output (guessing mass of total release) makes those sources look way worse than gas engines.
I'd be curious if particle size effects could be found in the studies' data. Unfortunately that might have to come from comparing a completely different populati
Remember leaded gasoline? (Score:2)
Lead added to gasoline contributed to a ton of mental health conditions across the United States until it was discontinued. Until the lead was banned, we had no idea of the widespread impact of the damage caused. It's entirely possible that the various brain disorders that the elderly encounter are made much worse by the pollutants in the air, and we won't know how badly we're being affected.
It's OK, industry was scared off to the 3rd world (Score:2)
A bigger problem is we don't have them any more !
That should not hinder people to exercise though (Score:1)