You'll get more benefit by walking a little further still—to around 7,700 steps a day—but after that you're just walking for walking's sake, say researchers from Harvard Medical School.
They looked at the walking habits of 16,741 women, with an average age of 72, who agreed to wear a tracking device that counted their steps. During the four years of the study, 504 of the women died—and they were the ones who moved the least, often averaging fewer than 2,700 steps a day. As the number of steps walked increased, the mortality level dropped until it plateaued at 7,700 steps.
"We were quite surprised that such a relatively small number of steps would be associated with such a substantial reduction in mortality," said researcher I-Min Lee.
The speed of walking didn't seem to be so significant. Many of the women strolled, and still saw the same health benefits as the few who walked more speedily.
The findings question the idea of walking 10,000 steps a day, which seems to have come from a Japanese clock maker who made an early pedometer whose name translates as "10,000 steps".