“If you could bottle all of these effects and put it in a pill, would we be in a different place now?”
That’s the question posed by Laura Baker, associate professor of Geriatric Medicine, Neurology and Public Health Sciences at Wake Forest School of Medicine. She was speaking at the Alzheimer’s Association International Conference in July.
Professor Baker was describing something that’s available to everyone, is free of charge, and is already known to reduce heart disease, stroke, diabetes, and the risk of some forms of cancer.
She explained that few top-quality studies have been conducted to see if it can reduce dementia risk. The audience listened attentively but then sat up and took note as she presented some dramatic findings from her new study.
Here’s what got their attention – and mine. . .
Professor Baker demonstrated that not only can dementia be stopped in its tracks, it can even be reversed by exercise.
Key Takeaways
- Regular aerobic exercise can reduce the risk of Alzheimer’s by up to 50% and prevent dementia onset.
- Exercise has been shown to increase brain size, improve blood flow, and reduce tau protein, which are markers of Alzheimer’s disease.
- Physical activity combats inflammation, strengthens blood vessels, and reduces amyloid plaques associated with cognitive decline.
Exercise Cuts Your Risk of Alzheimer’s in Nearly Half
Studies reveal that exercise does more than keep you fit; it’s a powerful tool for brain health, too. From shrinking tau proteins linked to Alzheimer's to improving blood flow and memory, exercise might be the closest thing we have to a brain-boosting "pill."
While it’s true that gold-standard studies are limited, nevertheless, 11 trials involving middle-aged people over time showed that regular exercise can reduce the risk of dementia by nearly a third and the risk of Alzheimer’s by almost half.
Aerobic Exercise is the Key
Over a shorter period of a month or so, 29 trials found that regular aerobic exercise like walking, running, cycling, and swimming wiped away brain fog and improved memory, attention, and processing speed.
Even among people over 60, 26 studies show better cognitive performance in those who keep physically active.
For her test of the concept, Professor Baker enrolled patients aged 55 to 89 with mild cognitive impairment, a condition that often leads to Alzheimer’s.
One group engaged in 45 minutes of aerobic exercise in a gym four times a week using a stationary exercise machine, bike, or treadmill. The aim was to reach about 70% of the maximum heart rate.
A second group performed gentle stretching exercises for 35% of the maximum heart rate. At the end of six months, she assessed both groups.
Reversed Mental Decline
The stretching group saw no cognitive benefits. Their brains continued to shrink, blood flow to the brain did not improve, the ability to carry out day-to-day tasks continued to go downhill, and tau protein levels in the brain that are associated with Alzheimer’s showed no improvement.
The story for the aerobic group was quite different.
They had a significant increase in brain size, blood flow to the brain increased, there were improvements in their ability to plan and carry out multiple tasks and daily activities without foggy thinking, and the level of tau protein decreased.
This was the most substantial evidence that exercise can treat early signs of dementia.
Helps Patients With Alzheimer's, Too
Professor Baker also conducted a study using the same exercise protocols but with 76 patients diagnosed with Alzheimer’s. Even among these advanced dementia cases, those in the aerobic group experienced a slower rate of memory decline than those in the group that merely did stretching exercises.
Among the aerobic exercisers, the hippocampus area of the brain that’s so crucial for retaining memories actually grew.
In an earlier interview, Professor Baker said exercise can modulate the risk of cognitive decline in several ways.
“Exercise exerts benefits on inflammation, improves the integrity of both macro and micro [blood] vessels, [and] has a beneficial effect on physical and psychological stress, all of which have been shown to have potent effects on amyloid [brain plaque] burden.”
It's Never Too Late
Dr. James Pickett, head of research at the Alzheimer’s Society, said, “This research suggests that it’s never too late to take up exercise.”
He’s right.
To answer Professor Baker's question, yes, we would be in a different place now if these benefits could be put into a pill. So, dust off those golf clubs or tennis rackets and ease yourself back into a sport. Or walk every day. It’s one of the healthiest activities there is, whether you're trying to wipe away those mental cobwebs and clear brain fog or reverse memory loss.
Summary
Exercise has emerged as a powerful ally in the fight against cognitive decline, with studies showing it may significantly reduce the risk of Alzheimer’s and even reverse early dementia symptoms. Professor Laura Baker’s research revealed that consistent aerobic exercise for just six months improved brain size, blood flow, and memory function among participants with mild cognitive impairment. The findings suggest that exercise not only prevents but could actively combat the progression of dementia by reducing amyloid plaques, lowering inflammation, and enhancing brain health overall.
Frequently Asked Questions
How much exercise is needed to benefit brain health?
Regular aerobic exercise, such as 45 minutes four times a week, can improve brain health and reduce dementia risk.Can exercise actually reverse dementia?
Studies show that aerobic exercise can reverse some symptoms in people with mild cognitive impairment, potentially slowing memory loss.What types of exercise are beneficial for cognitive health?
Aerobic activities like walking, cycling, swimming, and using an exercise machine have shown cognitive benefits.Does exercise help those already diagnosed with Alzheimer’s?
Yes, research shows even those with Alzheimer’s experience slower cognitive decline when participating in aerobic exercise.Is there an age limit for exercise to benefit the brain?
No, studies indicate that people over 60 who are physically active see cognitive benefits, and it’s never too late to start.
