What you've heard: You need 10,000 steps a day
Is 10,000 steps a day a myth? How many steps you actually need
A round number, not a threshold. Evidence grade: Probable.
Published Updated
The "What you've heard" box in Chapter 3
A round number, not a threshold
The evidence
The number has no documented scientific origin, and the usual story of where it came from traces to no primary source. The pooled cohorts found most of the benefit below it, at a point that depends on your age. The curves flattened without turning back up, so more is fine if you enjoy it; falling short of the round number is not failure.
Where the book tests it
What the book recommends instead
Walk every day, building toward 7,000 to 8,000 steps from wherever you are
StrongEvidence grade: Strong. Multiple randomized controlled trials, or consistent large cohort studies with a well-understood mechanism.for the curveProbableEvidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.for the exact numberHow: add a walk with a destination, to a shop or a friend's door, and lengthen it over weeks, not days. Under sixty, the gains keep coming up to about 8,000 to 10,000. Some of it should be brisk, about a hundred steps a minute (Chapter 1 gives a fifteen-second check). Why: the steepest drop in risk comes at the bottom, from about 3,000 steps to 5,000, so the least active gain the most.
Related claims
- Do barefoot shoes fix your feet?Probable for foot strength; unsupported for injury prevention.Evidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.
- Is sitting the new smoking?Exaggerated about tenfold.Evidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.
This verdict is one of the "What you've heard" boxes in Chapter 3, The Body That Walks, where the book tests the claims people repeat against the studies behind them. The grade rates the evidence behind the verdict, by the book's stated method.
Educational content, not medical advice. Disclaimer.