INTRODUCTION AND OBJECTIVE: The ketogenic diet (KD) is a high-fat, adequate-protein, low-carbohydrate diet that is getting more and more widespread in medicine. This dietary intervention causes changes in cerebral metabolism, which are considered potentially beneficial in patients with neurological disorders, but its impact should be controlled and assessed individually. The aim of this review is to provide an update of existing evidence concerning the utility of magnetic resonance spectroscopy (MRS) in monitoring shifts in the cerebral metabolism during ketogenic diet in patients with neurological disorders. REVIEW METHODS: The latest available literature was reviewed by May 13, 2021 using the PubMed, Web of Science and Google Scholar databases. There were 13 papers selected for analysis after reading the title, abstracts and whole text, meeting the assumed criteria. ABBREVIATED DESCRIPTION OF THE STATE OF KNOWLEDGE: MRS is a non-invasive imaging method providing information about the metabolism of brain tissues and playing an increasingly important role in monitoring the concentrations of cerebral metabolites in the course of such neurological disorders as primary brain tumour, epilepsy during KD. Recent trials prove that inverse correlation between serum β-hydroxybutyrate levels and N-acetylaspartate in brain tissue confirm antiepileptogenic properties of KD. Furthermore, ketone concentrations including β-hydroxybutyrate and acetone in both lesional and contralateral brain are referred to as correlating with average ketonuria in patients with primary brain tumou. SUMMARY: MRS is a feasible tool for detecting cerebral metabolic shifts linked to a ketogenic diet. However, further studies confirming MR spectroscopy utility in monitoring ketogenic diet treatment in patients with neurological disorders are needed.