How many steps must you take per day to cut your risk of dementia?

Often, when I call my 93 year old Mom, my sister tells me that she's busy "getting her steps."  Her Fit Bit (or whatever she's using these days) has given her a quota of steps to get in, and it's grading her on how well she's doing.  Usually, she's just walking around the house. 

In China, the government expects you to get in a certain number of steps per day, and they too will grade you on your performance.  With an aging population, dementia is an important consideration of the Chinese government.  This is why China is the second biggest funder of Alzheimer's research in the world.

It has become a feature of popular culture that we should all be getting between 5,000 and 8,000 steps in every day for optimal physical health -- depending on who you ask, and who you're talking about.

But where did these numbers come from, and are they right?

At least from the standpoint of protection from dementia, there is new research published in the journal JAMA Neurology finding that the right number could vary from 3,800 to 9,800 steps per day, if your target is dementia prevention.  Click here for CNN's assessment of the research. 

Why such a broad range?  It depends on how much you want to cut your risk.  People between the ages of 40 and 79 cut their risk by 50% by taking 9,800 steps, while those who took 3,800 steps cut their risk by 25%.  Those who walked "with purpose" (power walked at least 40 steps a minute for 6,315 steps) cut their risk by 57%.  And, according to the research, those who got in 10,000 steps cut their risk the most.

These are actually quite doable for most people, but numbers like 10,000 are kind of scary.  So a proposal is that we talk about 112 steps per minute, 30 minutes per day.  The 112 is less scary, but in the research, it exceeded the benefit of 10,000 steps.

This was actually a pretty remarkable study involving 78,000 tests subjects in the UK between the ages of 40 and 79.  They all wore a wrist accelerometer (a fancy word for a Fit Bit or similar device).  The data was used to identify how many steps people got in and at what pace.  Results were based on how many developed dementia of any kind within seven years.

These results should not surprise us.  As we said in Beating the Dementia Monster, I have been told by very knowledgeable researchers that physical exercise is the single most powerful weapon we have to fight both the onset and progress of Alzheimer's disease.  (This is followed by sleep adequacy, diet, and social connection.)

I have also read and been told by authoritative people that there is no treatment, either available or in the pipeline, that will cure Alzheimer's disease.  The best we can hope for is to combine treatments like Aduhelm or (if approved) lecanemab with each tool of our Dementia Toolkit to perhaps prevent, but significantly slow the progress of the disease.