The higher your daily step count, the lower your risk of death per year, according to a new analysis – but the link only goes so far.
We have long been encouraged to walk as a way of improving health, but many studies on its benefits have focused on people in their early 60s and have sometimes ignored minority ethnic groups.
A new analysis, by Pedro Saint-Maurice at the US National Cancer Institute and his colleagues, looked at 4840 people who were representative of the US population over the age of 40. Between 2003 and 2006, all participants wore an accelerometer for a week.
The team found that the average daily step count was 9,124 paces, higher than many previous studies. That may be because the study included younger people, those in less sedentary jobs and more men, who tend to be more active.
The researchers used 4,000 steps a day as their baseline – easily achieved by someone who drives to a desk job. By comparison, the team found that taking 8,000 steps was associated with a 51% lower risk of dying per year, and taking 12,000 daily steps was associated with a 65% lower risk.
But taking more than 12,000 steps did not seem to show a further reduction of mortality risk. Up until 12,000 steps, more paces equated to a lower risk of dying per year regardless of sex, race, level of education, health condition and whether a person smoked or drank alcohol. The intensity of the steps taken also had little to no effect on the mortality risk.
The unadjusted incidence density for all-cause mortality was:
- 76.7 per 1,000 person-years (419 deaths) for the 655 individuals who took less than 4,000 steps per day;
- 21.4 per 1,000 person-years (488 deaths) for the 1,727 individuals who took 4,000 to 7,999 steps per day;
- 6.9 per 1,000 person-years (176 deaths) for the 1,539 individuals who took 8,000 to 11,999 steps per day; and
- 4.8 per 1,000 person-years (82 deaths) for the 919 individuals who took at least 12,000 steps per day.
Compared with taking 4,000 steps per day, taking 8000 steps per day was associated with significantly lower all-cause mortality (HR, 0.49 [95% CI, 0.44-0.55]), as was taking 12 000 steps per day (HR, 0.35 [95% CI, 0.28-0.45]).
Murugesu, J.A. (2020) Higher Step Count Linked to Lower Annual Risk of Death. New Scientist. 04 April 2020, pp.20.
Saint-Maurice, P.F., Troiano, R.P., Bassett Jr, D.R., Graubard, B.I., Carslon S.A., Shiroma, E.J., Fulton, J.E. & Matthews, C.E. (2020) Association of Daily Step Count and Step Intensity With Mortality Among US Adults. JAMA Network. 323(12), pp.1151-1160. doi:10.1001/jama.2020.1382