Lower Mortality

In the world of step goals and activity trackers, the lower mortality number can sound like a magic one. Many wearable devices that track the number of steps a person takes each day come pre program with a daily goal of 10,000 steps. But while a large body of evidence shows that physical activity is good for a person’s health and longevity, few studies have examined how many steps a day are associated with good health, particularly long-term health outcomes.

Physical activity for health

Taking 10,000 steps a day can sound daunting. But we find that even a modest increase in steps taken is tied to significantly lower mortality in older women,” said I-Min Lee, MBBS, ScD, an epidemiologist in the Division of Preventive Medicine at the Brigham. Their study adds to a growing understanding of the importance of physical activity for health, clarifies the number of steps related to lower mortality and amplifies the message: Step more even a little more is helpful.

According to previous studies, the average number of steps take by people in the U.S. is between 4,000 and 5,000 per day. The origin of the 10,000 step goal is unclear; but may trace back to 1965, when a Japanese company began marketing a pedometer called Manpo-kei, which translates to “10,000 steps meter” in Japanese.

To conduct their study, Lee and colleagues include participants; so from the Women’s Health Study, a randomized trial originally conduct to evaluate risk of cardiovascular disease; also cancer among women taking low-dose aspirin and vitamin E. When the original trial ended, participants were invited to participate in a long-term observational study.

Greatest risk of death

Participants were followed for an average of more than four years; so during which time 504 women died. Participants in the bottom 25% of steps walked; so were at greatest risk of death, with 275 women dying. Those who walked modestly more (average of 4,400 per day) were at 41% lower risk of death. Risk of death continue to decrease with more steps walked; so up to 7,500 steps per day, after which risk leveled off.

The Women’s Health Study included primarily older, white women; also further studies will be need in younger and diverse populations to determine; so if the findings are applicable to other groups, especially those who may, on average, take more steps. Other outcomes such as quality of life and risk of specific diseases; so were not asses, but will be addressed in future studies.

Of course, no single study stands alone. But our work continues to make the case for the importance of physical activity, said Lee. Clearly, even a modest number of steps was relate to lower mortality rate among these older women. They hope these findings provide encouragement for individuals for whom 10,000 steps a day may seem unattainable.