It takes 20-30 years for the brain changes leading to Alzheimer’s to occur.
The very best lifestyle change a person can make in midlife to protect against cognitive decline later is taking more exercise.
The results come from a study of 387 women in Australia who were followed from 1992 when they were between 45 and 55-years-old.
They were followed for over 20 years.
The researchers recorded all sorts of lifestyle factors including:
- mood,
- smoking,
- marital and employment status,
- education,
- and diet.
Each person was given simple tests of memory, such as the ability to remember a list of ten unrelated items.
Dr Cassandra Szoeke, who led the study, said:
“We now know that brain changes associated with dementia take 20 to 30 years to develop.
The evolution of cognitive decline is slow and steady, so we needed to study people over a long time period.
We used a verbal memory test because that’s one of the first things to decline when you develop Alzheimer’s Disease.”
Out of all the lifestyle changes, the number one protective factor was exercise.
It didn’t matter what type — from walking the dog to climbing a mountain — exercise was the lifestyle factor that provided the greatest protective effect against memory loss.
Dr Szoeke said:
“The message from our study is very simple.
Do more physical activity, it doesn’t matter what, just move more and more often.
It helps your heart, your body and prevents obesity and diabetes and now we know it can help your brain.
It could even be something as simple as going for a walk, we weren’t restrictive in our study about what type.”
You should start as early as possible, Dr Szoeke said:
“We expected it was the healthy habits later in life that would make a difference but we were surprised to find that the effect of exercise was cumulative.
So every one of those 20 years mattered.
If you don’t start at 40, you could miss one or two decades of improvement to your cognition because every bit helps.
That said, even once you’re 50 you can make up for lost time.”
The study was published in the American Journal of Geriatric Psychiatry (Szoeke et al., 2016).