Use of monosodium glutamate in foods: the good, the bad, and the controversial side

Introduction: Monosodium glutamate (MSG) is known as a flavor-enhancing compound and also the fifth basic taste (umami). About the safety of using MSG as a food additive, some studies show indications that there is no threat and others show the opposite. There is no consensus about the advantages and disadvantages of using MSG. Objective: To systematically review studies in the international literature on the knowledge of the pros and cons of using glutamate in food. Methods: Systematic review of studies published in journals indexed in ScienceDirect and PubMed databases. Articles published until 2020 were included. The aspects involving the advantages and disadvantages were discussed, as well as the health risks related to the MSG intake from diet. Results: The revised studies showed that MSG can reduce the amount of sodium in foods without modifying flavor. Although authorities indicate that MSG is safe for human consumption, some studies highlight that health risk is real. The use of MSG is still controversial because there are some misunderstandings in the applied amounts of MSG absorption and metabolism. Conclusion: MSG is widely applied in industrial and homemade food. The need for further studies is crucial, and aspects such as metabolism and amounts of MSG effectively consumed must be better evaluated.