A Novel Chronotype-Based Mediterranean Diet Pyramid: An Updated Representation by the Italian Society of Endocrinology (SIE) and the Italian Society of Dietetics and Clinical Nutrition (ADI)

This review explores the integration of chronobiology and chronotype-specific factors into the Mediterranean Diet (MD) framework. While the MD is widely recognized for its cardiometabolic and neuroprotective effects, current guidelines do not address the timing of food intake or the influence of individual chronotype. Given the growing evidence linking circadian alignment, meal timing, and metabolic health, we propose a revised Mediterranean Diet pyramid tailored to chronotype and lifestyle determinants, herein referred to as the chronotype-based Mediterranean Diet Pyramid of the Italian Society of Endocrinology (SIE) and the Italian Society of Dietetics and Clinical Nutrition (ADI). Chrononutrition emphasizes the timing, frequency, and regularity of meals as key elements for metabolic regulation. Early-day energy intake, time-restricted eating, and alignment with circadian rhythms improve glycemic control, weight management, and cardiovascular outcomes. Morning chronotypes tend to show higher adherence to the MD, whereas evening chronotypes more frequently delay meals, skip breakfast, and consume energy-dense foods at night, contributing to poorer metabolic profiles. Sleep duration and quality further modulate appetite regulation and dietary adherence. Building on these insights, the proposed pyramid integrates circadian cues, represented by sun and moon symbols, to guide nutrient timing. Foods rich in carbohydrates and fiber (whole grains, legumes, fruits) are emphasized earlier in the day, while protein- and vegetable-based meals are prioritized in the evening, alongside sleep-promoting foods such as dairy, nuts, and seeds. Lifestyle pillars, including physical activity, adequate sleep, and the alignment of eating schedules with chronotype, form the foundation of the pyramid. The integration of chronobiological principles into the MD offers a novel paradigm that couples dietary quality with circadian alignment. A chronotype-oriented MD pyramid may enhance adherence, optimize metabolic flexibility, and reinforce the MD as a holistic model encompassing nutrition, lifestyle, and sustainability.