The famous goal of 10,000 steps a day was never based on science — it began as a 1960s marketing slogan for a Japanese pedometer, and research now finds most of the health benefits arrive well before you ever reach it

The number was round, it was easy to remember, and the kanji for 10,000 happens to look a bit like a person mid-stride. Harvard Medical School epidemiologist I-Min Lee has been unusually blunt about the whole thing, telling Popular Science that no studies had examined 10,000 steps at the time. Women averaging around 4,400 steps a day had a 41 per cent lower death rate than the least active group, who managed about 2,700, per the National Institutes of Health summary of the work. Compared with 2,000 steps a day, 7,000 came with a 47 per cent lower risk of dying from any cause, a 38 per cent lower dementia risk and a 28 per cent drop in falls. Obesity risk kept dropping as steps rose, in a straight line instead of a curve, with the sharpest separation above about 8,200 steps a day.