For the millions of adults navigating life after a cardiac event, the quality of nutritional guidance they receive during rehabilitation may be as consequential as the medications they take — yet this scoping review exposes a striking disconnect between how central nutrition is considered in cardiac rehab and how rigorously it has actually been studied.
Drawing from a systematic search across PubMed, Embase, Web of Science, and Cochrane Library spanning all records through June 2026, researchers screened 2,765 studies and retained 35 that met strict eligibility criteria: randomized and non-randomized trials plus observational studies, all involving explicitly described nutritional interventions within structured cardiac rehabilitation (CR) programs for adults with established cardiovascular disease. The interventions were heterogeneous, encompassing Mediterranean and heart-healthy dietary patterns, calorie-restriction protocols, comprehensive lifestyle programs, structured nutrition education, supplementation, functional foods, and individualized dietary prescriptions. Consistent benefits emerged for body weight, central adiposity, and adherence to cardioprotective dietary recommendations — notably stronger when programs involved repeated contact and individualized guidance. Effects on lipid profiles, inflammatory markers, and blood pressure showed less uniformity across studies.
This review arrives at a moment when personalized nutrition and cardiometabolic medicine are converging, making the evidence gaps it identifies particularly consequential. The finding that only 35 studies out of nearly 2,800 records met eligibility standards underscores how underpowered and methodologically inconsistent this field remains. The heterogeneity of interventions also makes pooling effect sizes statistically unreliable, which limits actionable clinical conclusions. Notably, the strongest and most replicable signals cluster around behavioral delivery factors — frequency of contact, individualization — rather than any single dietary pattern, suggesting implementation design may matter as much as dietary content. For health-conscious adults enrolled in or considering cardiac rehab, this signals that program structure and personalized follow-through, not just generic dietary advice, should be evaluated. Editorially, this review is confirmatory rather than paradigm-shifting: it validates longstanding clinical intuition about Mediterranean-style eating and individualized counseling while formally documenting the evidence void that has persisted far too long in this high-stakes population.
