Beyond Diabetes: Continuous Glucose Monitoring as a Candidate Precision Tool for Cardiovascular Prevention and Healthy Longevity—A Hypothesis-Generating Narrative Review

Background and Objectives: Cardiovascular disease remains the leading cause of premature mortality worldwide. Subclinical glucose dysregulation, a contributor to accelerated vascular aging, is undetectable by conventional screening in apparently healthy individuals; even within the normal glycemic range, postprandial glucose excursions promote endothelial injury and inflammatory pathways independently of mean glucose levels. Hypothesis: Continuous glucose monitoring (CGM)-guided metabolic phenotyping, combined with personalized dietary optimization, structured fasting protocols, and selective longevity-oriented pharmacotherapy, constitutes a mechanistically coherent, hypothesis-generating preventive strategy that may attenuate cardiovascular risk and biological aging in apparently healthy non-diabetic adults, pending confirmation in prospective outcome trials. Materials and Methods: This narrative review synthesizes evidence from prospective cohort studies, randomized controlled trials, and mechanistic investigations connecting CGM-guided metabolic assessment with preventive cardiology and the emerging field of longevity medicine, focusing on glycemic variability biology, nutrient-sensing pathways, and the cardiovascular and longevity profiles of low-dose metformin and acarbose. Results: CGM-derived metrics capture inter-individual glycemic variability invisible to standard assessments and provide behavioral feedback for dietary personalization. Structured fasting and low-dose metformin converge on shared nutrient-sensing pathways implicated in both vascular aging and longevity, with CGM enabling objective confirmation of metabolic adaptation. Acarbose has shown cardiovascular and lifespan benefit signals in secondary trial analyses and preclinical longevity models, though these findings require replication and are not yet established in non-diabetic populations. Conclusions: We propose a four-phase research framework integrating CGM metabolic phenotyping, dietary optimization, fasting titration, and selective pharmacological augmentation for apparently healthy adults at cardiovascular risk. Prospective hard-endpoint trials are lacking, and this framework should be regarded as hypothesis-generating rather than an established clinical strategy, warranting rigorous outcome-based evaluation before clinical adoption.