Early Biomarkers, Risk Factors, and Functional Indicators of Healthy Longevity and Their Relationship with Diet
This narrative review associates dietary patterns — particularly the Mediterranean diet — with clinical and functional determinants of healthy aging, but the direction of effects is favorable only for selected outcomes and is supported predominantly by observational evidence.
| Outcome | Grade | Direction | Effect | Studies |
|---|---|---|---|---|
| LDL Cholesterol | B | ▲ Favorable | Redução ~29.6% LDL-C com portfólio alimentar; redução 25% eventos CV com intervenções dietéticas; IC 95% não reportado | — |
| Major vascular events | B | ▲ Favorable | RR redução 22% por -1 mmol/L LDL-C (estatina, seguimento 5 anos); IC 95% não reportado | — |
| Body weight and anthropometric parameters | C | ▲ Favorable | Associação consistente dieta mediterrânea vs dieta ocidental; magnitude e IC não quantificados na revisão | — |
| Muscle mass / sarcopenia | C | ▲ Favorable | Associação observacional entre ingestão proteica/leucina e preservação de massa muscular; sem tamanho de efeito reportado | — |
| Cognitive function | C | ▲ Favorable | Dados predominantemente observacionais; sem tamanho de efeito ou IC reportados | — |
| Sleep quality | C | — Insufficient | Evidência observacional escassa; sem tamanho de efeito reportado | — |
| Blood pressure | B | ▲ Favorable | Associação favorável com padrões plant-based/mediterrâneo; magnitude específica não consolidada na revisão | — |
Context
Healthy longevity depends on multiple modifiable determinants — body weight, lipid profile, glycemia, blood pressure, sleep, cognitive and physical function — that interact with diet across the lifespan. Heterogeneity in study designs and the difficulty of isolating the effect of individual nutrients from overall dietary patterns limit direct clinical translation. The review integrates evidence from cohorts, RCTs, and meta-analyses to guide clinicians and researchers.
What the study showed
Each 1 mmol/L reduction in LDL-C through statin therapy was associated with a 22% reduction in major vascular events over a median 5-year follow-up; diverse dietary interventions produced a 25% reduction in cardiovascular event rates. A combination of cholesterol-lowering foods (plant sterols, soy protein, viscous fibers, nuts) reduced LDL-C by approximately 29.6% over the same period. The Mediterranean diet showed the most consistent association with anthropometric and cardiometabolic parameters compared to other patterns, although RCTs show heterogeneity in the magnitude and duration of effect. Data on cognitive function, sleep, and physical performance are predominantly observational and do not support robust causal inference.
How it was done
Narrative review without a registered systematic protocol, without quantitative synthesis, and without formal risk-of-bias assessment tools. The search covered PubMed/MEDLINE, Web of Science, and Scopus through November 2025, prioritizing studies from the last 10–15 years. Cohorts, RCTs, meta-analyses, and mechanistic studies published in English were included.
Effect magnitude
An overall effect size is not calculable: the narrative review aggregates heterogeneous studies without meta-analysis. The only explicit magnitude datum is the ~29.6% reduction in LDL-C with a cholesterol-lowering food portfolio, with no 95% CI reported.
Limitations
Narrative review without PROSPERO registration, without formal risk-of-bias assessment (RoB 2, ROBINS-I, or AMSTAR-2), and without quantitative synthesis, introducing high risk of selection and confirmation bias. Most reported associations derive from observational studies subject to residual confounding and reverse causality. Heterogeneity in dietary assessment methods, study populations, and measured outcomes prevents direct comparisons. The 'obesity paradox' in older adults and the limitations of BMI as an adiposity proxy are acknowledged but not resolved.
In clinical practice
Clinicians can recommend high-vegetable-density dietary patterns (Mediterranean model or equivalent) as a cardiometabolic risk-reduction strategy, based on level-B evidence for LDL-C and blood pressure. For outcomes such as cognition, sleep, and body composition in older adults, evidence is insufficient for specific recommendations based on isolated nutrients. Adequate protein and leucine intake for muscle mass preservation in older adults warrants clinical attention, although evidence is predominantly observational.
What is still missing
Longitudinal studies integrating biological aging biomarkers (epigenetic clocks, telomeres) with controlled dietary interventions are needed. Long-duration RCTs with standardized functional outcomes in diverse aging populations remain scarce.