# A Narrative Review of Metabolomic Insights into Olive Oil's Nutritional Value
## 5 Challenges and Future Directions
In this context, integrated approaches combining metabolomics with other disciplines and longitudinal studies are needed to gain deeper insights into the health impacts of olive oil and to address challenges such as authenticity and quality assurance. In recent years, a novel technique for metabolite profiling and analysis of their involvement in metabolic pathways has emerged: metabolic flux analysis (MFA). This method includes two common approaches, which are flux balance analysis (FBA) and \({}^{13}\)C-metabolic flux analysis (\({}^{13}\)C MFA). While the former involves modeling metabolic reactions as a set of linear equations, the later uses \({}^{13}\)C-labeled substrates combined either with MS or NMR spectroscopy to analyze isotopic labeling patterns [98]. To our knowledge, MFA has not yet been applied in any studies assessing the health benefits of olive oil. Nevertheless, we believe that it could be crucial for helping the scientific community better understand the pathways that the bioactive compounds of this fundamental ingredient of olive oil enters in the human body. Conducting longitudinal studies to track the changes in metabolic profiles over time in response to olive oil consumption can provide valuable insights into its long-term health effects. By analyzing metabolomic data at multiple time points, researchers can identify the biomarkers associated with olive oil intake and their impact on various physiological processes such as inflammation, oxidative stress, and lipid metabolism, as described previously [99]. Integrating metabolomics with other -omics technologies such as genomics, transcriptomics, and proteomics should offer a comprehensive understanding of the molecular mechanisms underlying the health effects of olive oil. By correlating changes in metabolite levels with genetic variation, gene expression patterns, and protein profiles, researchers can identify novel pathways and biological targets influenced by olive oil consumption. Future research on olive oil metabolomics can also employ nutrigenomic approaches to investigate how genetic variation affects individual responses to olive oil consumption through the identification of gene-diet interactions. Thus, it is possible to personalize dietary recommendations and optimize health outcomes based on genetic profiles. Another important aspect is the implementation of clinical trials downstream of the study and development process for olive oil metabolomics. This would allow the health potential of longitudinal studies and meta-analyses to be directly highlighted, thereby capturing the real purpose of these studies to have an impact on human health. As previously mentioned, the PREDIMED trial demonstrated that the daily consumption of 50 g or more of polyphenol-rich EVOO as part of the MD could reduce CVD morbidity and mortality in high-risk individuals [100]. Several other sub-studies within PREDIMED analyzed the plasma metabolites related to CVD risk and EVOO consumption. Among the metabolites analyzed, ceramide was associated with CVD prevention after 7.4 years of treatment, demonstrating the modulation of the risk of disease. Another clinical trial regarding the role of VOO in HDL functionality reported the impact of some metabolites (i.e., phenolic compounds) of VOO on the HDL triacylglycerol levels. Finally, a postprandial clinical trial involving the consumption of 40 mL of EVOO rich in oleocanthal demonstrated the anti-aggregation properties of the olive oil metabolite [97]. Postprandial studies are interesting investigations that explore the post-meal metabolomic response to olive oil consumption, revealing differences in the serum metabolite profiles compared with other edible oils. Such studies have highlighted the potential of metabolomics to distinguish between different oil types and understand their physiological effects.