INTERMITTENT FASTING AND METABOLIC HEALTH: EVIDENCE FROM CLINICAL STUDIES
DOI:
https://doi.org/10.31435/ijitss.3(51).2026.6170Keywords:
Alternate-day Fasting, Body Composition, Intermittent Fasting, Metabolic Risk, Metabolism, Time-restricted EatingAbstract
Background: While overweight and obesity currently affect more than 1.9 billion adults worldwide and represent major risk factors for the development of metabolic diseases, intermittent fasting (IF), also referred to as intermittent energy restriction (IER), is a dietary strategy characterized by the alternation of periods of habitual food and drink consumption with periods of voluntary fasting or substantial energy restriction.
Aim: This review aims to analyze recent evidence regarding the effects of intermittent fasting in comparison with conventional dietary recommendations in overweight and obese individuals. The objective is to provide evidence-based insights that may assist clinicians and patients in determining whether intermittent fasting constitutes a feasible and effective alternative to traditional dietary interventions for optimizing metabolic health and reducing the risk of chronic disease development.
Methods: To conduct this review, Pubmed and Google Scholar were searched independently for relevant articles. Numerous studies were reviewed, followed by an in-depth analysis, and compilation of their implications in health and disease.
Results: Intermittent fasting (IF) is generally as effective as, but not necessarily superior to, traditional daily caloric restriction (DCR) for weight loss.
Conclusions: While the short-term benefits (typically 3–6 months) are well-documented, there is a consensus that more high-quality, long-term randomized controlled trials (12 months or longer) are required. Further research is needed to evaluate IF’s impact on hard clinical endpoints such as cardiovascular events, mortality, and its long-term safety in diverse or high-risk populations.
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Copyright (c) 2026 Adam Skrobarczyk, Karolina Rycman, Izabella Sośniak, Agnieszka Dobrowolska, Zuzanna Drewniak, Marta Rząsa, Kamil Wendrychowicz, Filip Wróbel
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