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. 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). 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). 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. National Health and Medical Research Council, New South Wales Health, and Ian Potter Foundation.

There is growing evidence that breastfeeding has short- and long-term cardiovascular health benefits for mothers. The objectives of this systematic review were to examine the association between breastfeeding and maternal cardiovascular risk factors and outcomes that have not previously been synthesized systematically, including metabolic syndrome, hypertension and cardiovascular disease. This systematic review meets PRISMA guidelines. The MEDLINE, EMBASE and CINAHL databases were systematically searched for relevant publications of any study design from the earliest publication date to March 2016. The reference lists from selected articles were reviewed, and forward and backward referencing were conducted. The methodological quality of reviewed articles was appraised using validated checklists. Twenty-one studies meeting the inclusion criteria examined the association between self-reported breastfeeding and one or more of the following outcomes: metabolic syndrome/metabolic risk factors (n = 10), inflammatory markers/adipokines (n = 2), hypertension (n = 7), subclinical cardiovascular disease (n = 2), prevalence/incidence of cardiovascular disease (n = 3) and cardiovascular disease mortality (n = 2). Overall, 19 studies (10 cross-sectional/retrospective, 9 prospective) reported significant protective effects of breastfeeding, nine studies (3 cross-sectional/retrospective, 5 prospective, 1 cluster randomized controlled trial) reported non-significant findings and none reported detrimental effects of breastfeeding. In most studies reporting significant associations, breastfeeding remained associated with both short- and long-term maternal cardiovascular health risk factors/outcomes, even after covariate adjustment. Findings from several studies suggested that the effects of breastfeeding may diminish with age and a dose-response association between breastfeeding and several metabolic risk factors. However, further longitudinal studies, including studies that measure exclusive breastfeeding, are needed to confirm these findings. The evidence from this review suggests that breastfeeding is associated with cardiovascular health benefits. However, results should be interpreted with caution as the evidence gathered for each individual outcome was limited by the small number of observational studies. Additional prospective studies are needed. CRD42016047766.

Background: Social media platforms are frequently used in health communication campaigns. Common understandings of campaign effects posit a sequential and linear series of steps from exposure to behavior change, commonly known as the hierarchy of effects model (HOE). These concepts need to be reevaluated in the age of social media, which are interactional and communal. Objective: This review aims to update the traditional HOE for health communication campaigns in the context of social media, including identifying indicators of effectiveness and how these are conceptualized to lead to health-related outcomes. Methods: We conducted a systematic review of studies following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines reporting on the use of social media as part of health communication campaigns, extracting campaign information such as objectives, platforms used, and measures of campaign performance. We used these data, combined with our understanding of the HOE, to develop an updated conceptual model of social media campaign effects. Results: We identified 99 eligible studies reporting on 93 campaigns, published between 2012 and 2022. The campaigns were conducted in over 20 countries, but nearly half (n=42) were conducted in the United States. Campaigns targeted a variety of health issues and predominantly used Facebook, Twitter, Instagram, and YouTube. Most campaigns (n=81) set objectives targeting awareness or individual behavior change. Process measures (n=68; eg, reach and impressions) and engagement measures (n=73; eg, likes and retweets) were reported most frequently, while two-fifths (n=42) did not report any outcomes beyond engagement, such as changes in knowledge, behavior, or social norms. Most campaigns (n=55) collected measures that did not allow them to determine if the campaign objective had been met; that is, they were process evaluations only. Based on our review, our updated model suggests that campaign exposure can lead to individual behavior change and improved health outcomes, either through a direct or indirect pathway. Indirect pathways include exposure through social and policy changes. “Engagement” is positioned as critical to success, replacing awareness in the traditional HOE, and all types of engagement are treated as equal and good. No consideration is being given to potential negative engagement, such as the distribution of misinformation. Additionally, the process is no longer linear and sequential, with circular pathways evident, such as engagement not only influencing behavior change but also generating additional exposure to campaign messages. Conclusions: Our review has highlighted a change in conventional understandings of how campaigns can influence health outcomes in the age of social media. The updated model we propose provides social media campaigners with a starting point to develop and tailor campaign messages and allows evaluators to identify critical assumptions to test, including the role and value of “engagement.” Trial Registration: PROSPERO CRD42021287257; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=287257

Objectives To examine independent and interactive associations of physical activity and diet with all-cause, cardiovascular disease (CVD) and physical activity, diet and adiposity-related (PDAR) cancer mortality. Methods This population-based prospective cohort study (n=346 627) is based on the UK Biobank data with linkage to the National Health Service death records to 30 April 2020. A left-truncated Cox proportional hazards model was fitted to examine the associations between exposures (self-reported total moderate-to-vigorous intensity physical activity (MVPA), vigorous-intensity physical activity (VPA) and a diet quality index (score ranged 0–3)) and outcomes (all-cause, CVD and PDAR cancer mortality). Results During a median follow-up of 11.2 years, 13 869 participants died from all causes, 2650 from CVD and 4522 from PDAR cancers. Compared with quartile 1 (Q1, 0–210 min/week), Q2–Q4 of MVPA were associated with lower risks of all-cause (HR ranged from 0.87 (95% CI: 0.83 to 0.91) to 0.91 (95% CI: 0.87 to 0.96)), CVD (HR ranged from 0.85 (95% CI: 0.76 to 0.95) to 0.90 (95% CI: 0.81 to 1.00)) and PDAR cancer mortality (HR ranged from 0.86 (95% CI: 0.79 to 0.93) to 0.94 (95% CI: 0.86 to 1.02)). Compared with no VPA, any VPA was associated with lower risk for all-cause and CVD mortality (HR ranged from 0.85 (95% CI: 0.80 to 0.89) to 0.88 (95% CI: 0.84 to 0.93) and from 0.75 (95% CI: 0.68 to 0.83) to 0.90 (95% CI: 0.80 to 1.02), respectively). Although not reaching statistical significance for all-cause and CVD mortality, being in the best dietary category (diet quality index=2–3) was associated with a reduction in PDAR cancer mortality (HR=0.86, 95% CI: 0.78 to 0.93). No additive or multiplicative interactions between physical activity categories and dietary quality was found. When comparing across physical activity and diet combinations, the lowest risk combinations consistently included the higher levels of physical activity and the highest diet quality score. Conclusions Adhering to both quality diet and sufficient physical activity is important for optimally reducing the risk of mortality from all causes, CVD and PDAR cancers.

There is growing evidence for a relationship between fruit and vegetable consumption and all-cause mortality. Few studies, however, specifically explored consuming raw versus cooked vegetables in relation to health and mortality outcomes. The purpose of this study was to examine the relation of all-cause mortality with: a) fruit and vegetable consumption, either combined or separately; b) the consumption of raw versus cooked vegetables in a large cohort of Australian middle-aged and older adults. The sample included 150,969 adults aged 45 years and over from the 45 and Up Study, a prospective cohort study conducted in New South Wales, Australia. Self-reported baseline questionnaire data (2006–09) were linked to mortality data up to June 2014. Fruit and vegetable consumption was assessed by validated short questions. Crude and adjusted hazard ratios were calculated using Cox proportional hazard models. Covariates included socio-demographic characteristics, health-related and dietary variables. During a mean follow-up of 6.2 years, 6038 (4 %) participants died from all causes. In the fully adjusted models, increasing consumption of fruit and vegetables combined was associated with reductions in all-cause mortality, with the highest risk reduction seen up to 7 serves/day or more of fruit and vegetables (P for trend = 0.002, hazard ratio for highest versus lowest consumption quartile: 0.90; 95 % confidence interval: 0.84, 0.97). Separate consumption of fruit and vegetables, as well as consumption of raw or cooked vegetables, were associated with a reduced risk of all-cause mortality in the crude and minimally adjusted models (all P for trend <0.05). With the exception of raw vegetables, these associations remained significant in the fully adjusted models (all P for trend <0.05). Age and sex were significant effect modifiers of the association between fruit and vegetable consumption and all-cause mortality. Fruit and vegetable consumption were inversely related to all-cause mortality in this large Australian cohort. Further studies examining the effects of raw versus cooked vegetables are needed.

Objectives Growing evidence suggests a link between diet and mental health. This study aimed to investigate the association between fruit and vegetable consumption and the prevalence and incidence of psychological distress in middle-aged and older Australians. Design Cross-sectional and prospective. Setting New South Wales, Australia. Methods A sample of 60 404 adults aged ≥45 years completed baseline (2006–2008) and follow-up (2010) questionnaires. Psychological distress was assessed at baseline and follow-up using the validated Kessler Psychological Distress Scale (K10), a 10-item questionnaire measuring general anxiety and depression. Psychological distress was defined as the presence of high-to-very high levels of distress (K10 score ≥22). Usual fruit and vegetable consumption was assessed using short validated questions. The association between baseline fruit and vegetable consumption and the prevalence or incidence of psychological distress was examined using logistic regression models. Results At baseline, 5.6% reported psychological distress. After a mean 2.7 years of follow-up, 4.0% of those who did not report distress at baseline reported distress at follow-up. Baseline fruit and vegetable consumption considered separately or combined, was associated with a lower prevalence of psychological distress even after adjustment for sociodemographic characteristics and lifestyle risk factors. Baseline fruit and vegetable consumption, measured separately or combined, was associated with a lower incidence of psychological distress in minimally adjusted models. Most of these associations remained significant at medium levels of intake but were no longer significant at the highest intake levels in fully adjusted models. Conclusions Increasing fruit and vegetable consumption may help reduce psychological distress in middle-aged and older adults. However, the association of fruit and vegetable consumption with the incidence of psychological distress requires further investigation, including the possibility of a threshold effect between medium and higher consumption levels.