Objectives: The aim of this study was to evaluate the effectiveness of health promotion interventions in delaying telomere shortening (a biomarker for aging). Data Source: PubMed, PsychINFO, EMBASE, CINAHL, and Cochrane Library databases. Study Inclusion and Exclusion Criteria: Inclusion criteria: (1) empirical studies involving human subjects; (2) health promotion intervention studies including both randomized control trials (RCTs) and non-RCTs.; (3) measured telomere length as an intervention outcome; and (4) were written in English. Exclusion criteria: (1) observational studies without any health promotion intervention practices and (2) did not report intervention effects. Data Extraction: Data extraction was performed by two reviewers following the preferred reporting items for systematic reviews and meta-analysis guidelines. Data Synthesis: Substantial heterogeneity in intervention type and study design in the included studies precluded a meta-analysis. We conducted a narrative synthesis instead. Results: Thirty studies were included in the review, of which 16 were RCTs. One-third of the included studies reported significant intervention impacts in delaying telomere shortening, with relatively consistent significant results emerged from weight-loss interventions and interventions involving multiple lifestyle modification components (eg, diet and exercise). Most of supplement intervention studies observed null effects in telomere length. Conclusions: Weight-loss and comprehensive lifestyle intervention strategies show encouraging impacts in delaying telomere shortening. More rigorous studies targeting populations at different age stages through life span are needed.