10/13/2026
Where did 10,000 steps a day come from? Not from a study. In this TEDx talk, Dr. I-Min Lee (professor of medicine at Harvard Medical School and of epidemiology at Harvard's school of public health) traces it to Japan in 1965, when a company sold a pedometer called the Manpo-kei: the "10,000 steps meter". Her own paper words it carefully: the goal "likely derives" from that trade name.
So her team tested it. 16,741 US women, average age 72, wore a tracker for a week and were followed for about four years. Women at about 4,400 steps a day had lower death rates than women at about 2,700. Rates kept falling with more steps, then leveled off at about 7,500.
The catch: that is one study of older women, it counted deaths only, and it is observational, so it can't prove the steps were the cause (healthier people also walk more). The level-off point moves with age: a 2022 analysis of 15 studies put it at about 6,000 to 8,000 steps for people 60 and over, and 8,000 to 10,000 for younger adults. And in an NIH study of adults 40 and over, compared with 4,000 steps, the risk of dying was 50% lower at 8,000 and 65% lower at 12,000. So 10,000 isn't wrong. It just isn't a pass mark.
The useful part, in her words: some stepping is good, more is better up to a certain point. The CDC says some physical activity is better than none, and that people with a chronic condition or a disability should ask a health professional which types and amounts of activity suit them.
What's your real daily number, and where do most of your steps come from? Send this to the friend who paces the kitchen at 11 pm to hit the goal.
Sources in the pinned comment. Video: TEDx Talks.
General wellness education only - not medical advice.