Andy
Senior Member (Voting rights)
Summary
Background
Despite the rapid increase in evidence from the past decade on daily steps and health-related outcomes, existing systematic reviews primarily focused on few outcomes, such as all-cause mortality. This study synthesised the prospective dose-response relationship between daily steps and health outcomes including all-cause mortality, cardiovascular disease, cancer, type 2 diabetes, cognitive outcomes, mental health outcomes, physical function, and falls.Methods
For this systematic review and meta-analysis, we searched PubMed and EBSCO CINAHL for literature published between Jan 1, 2014, and Feb 14, 2025, supplemented by other search strategies. Eligible prospective studies examined the relationship between device-measured daily steps and health outcomes among adults without restrictions on language or publication type. Pairs of reviewers (BN, KO, ML, and TN) independently did the study selection, data extraction, and risk of bias assessment using the 9-point Newcastle-Ottawa Scale. Hazard ratios (HRs) from individual studies were synthesised using random-effects dose-response meta-analysis where possible. Certainty of evidence was assessed using GRADE. This trial is registered with PROSPERO (CRD42024529706).Findings
57 studies from 35 cohorts were included in the systematic review and 31 studies from 24 cohorts were included in meta-analyses. For all-cause mortality, cardiovascular disease incidence, dementia, and falls, an inverse non-linear dose-response association was found, with inflection points at around 5000–7000 steps per day. An inverse linear association was found for cardiovascular disease mortality, cancer incidence, cancer mortality, type 2 diabetes incidence, and depressive symptoms. Based on our meta-analyses, compared with 2000 steps per day, 7000 steps per day was associated with a 47% lower risk of all-cause mortality (HR 0·53 [95% CI 0·46–0·60]; I2=36·3; 14 studies), a 25% lower risk of cardiovascular disease incidence (HR 0·75 [0·67–0·85]; I2=38·3%; six studies), a 47% lower risk of cardiovascular disease mortality (HR 0·53 [0·37–0·77]; I2=78·2%; three studies), a non-significant 6% lower risk of cancer incidence (HR 0·94 [0·87–1·01]; I2=73·7%; two studies), a 37% lower risk of cancer mortality (HR 0·63 [0·55–0·72]; I2=64·5%; three studies), a 14% lower risk of type 2 diabetes (HR 0·86 [0·74–0·99]; I2=48·5%; four studies), a 38% lower risk of dementia (HR 0·62 [0·53–0·73]; I2=0%; two studies), a 22% lower risk of depressive symptoms (HR 0·78 [0·73–0·83]; I2=36·2%; three studies), and a 28% lower risk of falls (HR 0·72 [0·65–0·81]; I2=47·5%; four studies). Studies on physical function (not based on meta-analysis) reported similar inverse associations. The evidence certainty was moderate for all outcomes except for cardiovascular disease mortality (low), cancer incidence (low), physical function (low), and falls (very low).Interpretation
Although 10 000 steps per day can still be a viable target for those who are more active, 7000 steps per day is associated with clinically meaningful improvements in health outcomes and might be a more realistic and achievable target for some. The findings of the study should be interpreted in light of limitations, such as the small number of studies available for most outcomes, a lack of age-specific analysis and biases at the individual study level, including residual confounding.Open access