The Role of Nutritional Ketosis in Managing Neurological Symptoms in Long COVID Patients: A Systematic Review
Abstract
Background: Long COVID is characterized by persistent neurological symptoms, which include cognitive dysfunction, fatigue, and memory problems. It is considered to be caused by chronic neuroinflammation and mitochondrial dysfunction. Current therapies are very unsatisfactory; therefore, there is an urgent need for novel therapeutic options. Among potential non-pharmacological strategies, nutritional ketosis induced by a ketogenic diet represents an appealing approach thanks to its neuroprotective and anti-inflammatory properties.
Aim: This systematic review will provide a critical appraisal of the evidence and theoretical rationale on the use of nutritional ketosis in the management of neurological symptoms among Long COVID patients.
Methods: A systematic search was performed in the databases PubMed, Scopus, Web of Science, PsycINFO, and Cochrane Library for studies published between 2013 and 2025. Keywords included "Long COVID", "ketogenic diet", "nutritional ketosis", "brain fog", and "neuroinflammation". Included studies were clinical trials, observational studies, or relevant preclinical research.
Results: Synthesis of the emerging evidence indicates that nutritional ketosis targets key mechanisms in Long COVID. Ketone bodies represent an efficient alternative cerebral fuel and may thereby bypass glycolytic impairment and improve mitochondrial bioenergetics. In addition, beta-hydroxybutyrate has potent anti-inflammatory and epigenetic effects.
Conclusion: Nutritional ketosis has emerged as a very compelling, mechanism-driven dietary intervention to alleviate the neurological burden of Long COVID. Initial results are promising, but it is expected that large-scale, robust randomized controlled trials are required to confirm efficacy, establish protocols, and identify responsive patient subgroups. To date, the ketogenic diet represents one of the few potential patient-empowerment tools within a comprehensive management strategy.
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Authors
Copyright (c) 2025 Khalid Abdulaziz Almehamad, Khaled Saleh Alkhaleefah, Yazeed Abdularahman Juwaid , Mohammed Ahmed Alzahrani, Abdulaziz Saad Alhazzaa, Mohammed Moteq Alharbi, Abdulaziz Mohammad Alarfaj, Saleh Ibrahim Mohammed Alhabib, Abdulrahman Nasser Aleid, Emad Abdullah Alreshoodi
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