Increasing Life Expectancy with Plant Polyphenols: Lessons from the Mediterranean and Japanese Diets

Abstract

Plant polyphenols have emerged as potent bioactive molecules that can modulate key cellular pathways associated with aging and chronic disorders. The Mediterranean diet and the traditional Japanese style of life are rich in polyphenol-containing foods and beverages, and epidemiological evidence links these dietary patterns to increased longevity and reduced morbidity. This narrative review examines the chemical description of plant polyphenols, their mechanisms of action, including anti-inflammatory, antioxidant, and hormetic effects, and how supplementation or a diet rich in these compounds may provide further life extension. We discuss the major classes of polyphenols present in the Mediterranean dietary pattern (e.g., resveratrol and hydroxytyrosol) and in the Japanese diet (e.g., epigallocatechin gallate and soy isoflavones), comparing their biological behaviors and cooperative effects on metabolic, cardiovascular, and neurodegenerative conditions. We also examine a few preclinical and clinical studies that explain the beneficial impact of these chemicals on aging-associated biomarkers. Furthermore, both dietary habits are characterized by low consumption of processed foods and sugary carbonated drinks and reduced utilization of deep-frying with linoleic acid-rich oils, a practice that reduces the formation of harmful lipid peroxidation products, notably 4-hydroxynonenal, known to be implicated in accelerating the aging process. The Mediterranean dietary pattern is also characterized by a low/moderate daily consumption of wine, mainly red wine. This work debates emerging evidence addressing issues of bioavailability, dosage optimization, and formulation technologies for polyphenol supplementation, also comparing differences and similarities with the vegan and vegetarian diets. We also explore how these chemicals could modulate epigenetic modifications that affect gene expression patterns pertinent to health and aging. In conclusion, we aim to show a consolidated framework for the comprehension of how plant polyphenols could be utilized in nutritional strategies for potentiating life expectancy while stimulating further research on nutraceutical development.

Keywords: Japanese diet; aging; antioxidants; longevity; mediterranean diet; nutraceuticals; plant polyphenols; vegan diet; vegetarian diet.

Figure 1

Polyphenol pathways and aging. NF-kB (nuclear factor kappa-light-chain-enhancer of activated B cells); mTOR (mammalian target of rapamycin); AMPK (5′ AMP-activated protein kinase); SIRT1 (sirtuin 1); Nrf2 (nuclear factor erythroid 2-related factor 2). Servier Medical Art by Servier is licensed under a Creative Commons Attribution 3.0 Unported License (https://creativecommons.org/licenses/by/3.0/, accessed on 29 June 2025). ↑ indicates elevation. ↓ indicates reduction.

Figure 2

Relationship between Mediterranean and Japanese polyphenol contents. The Mediterranean and Japanese diets are both associated with exceptional health benefits and longevity, and a key shared feature is their high content of polyphenols. However, these diets differ in polyphenol sources, types, and patterns of consumption, leading to distinct metabolic profiles and potentially complementary effects on aging and disease prevention. EGCG, epigallocatechin gallate. Parts of the figure were drawn by using pictures from Servier Medical Art and Microsoft PowerPoint 365 Version 2112 (https://www.microsoft.com/microsoft-365, accessed on 29 June 2025). Servier Medical Art by Servier is licensed under a Creative Commons Attribution 3.0 Unported License (https://creativecommons.org/licenses/by/3.0/, accessed on 29 June 2025).