Methylmercury (MeHg) contamination in seafood poses significant health risks, particularly neurotoxicity, to human populations worldwide. Selenium acts as a protector against the toxicity of metals such as mercury and inorganic arsenic [1], but at the same time, the loss of Se bioavailability caused by these pollutants must be considered. New criteria have been proposed to assess the risks of Hg exposure, namely the Se Health Benefit Value (HBVSe) and the Benefit–Risk Value (BRV), which allows for the simultaneous evaluation of Hg exposure and dietary Se intake. Additionally, changes in mercury bioaccessibility have been attributed to cooking, which changes the conformation of native proteins [2]. Various studies have shown that the benefits of consuming seafood outweigh the risks, especially when the protective effects of selenium are considered. This comprehensive review examines the biomolecular interactions underlying the protective effects of selenium against MeHg in the human body. We will discuss the mechanisms by which selenium modulates MeHg toxicity, including its role in mitigating oxidative stress, preventing MeHg bioaccumulation, and facilitating detoxification pathways. Nevertheless, further research in this area is necessary to study the synergistic effects between the different variables to improve the understanding of the repercussions of fish and shellfish intake on health. Future research directions are proposed to elucidate the protective role of selenium against methylmercury toxicity and inform public health policies and interventions. Overall, this communication contributes to our understanding of the complex interplay between selenium and methylmercury in the human body and underscores the potential of selenium as a therapeutic agent for mitigating MeHg-related health risks.

1. Melgar, M.J, Selenium intake from tuna in Galicia (Spain): Health risk assessment and protective role against exposure to mercury and inorganic arsenic. Sci Total Environ, 2019. 694: p. 133716.
2. Torres-Escribano, S., Mercury and methylmercury bioaccessibility in swordfish. Food additives & contaminants, 2010. 27: p. 327-37