A Review of the Alleged Health Hazards of Monosodium Glutamate

Abstract

Monosodium glutamate (MSG) is an umami substance widely used as flavor enhancer. Although it is generally recognized as being safe by food safety regulatory agencies, several studies have questioned its long‐term safety. The purpose of this review was to survey the available literature on preclinical studies and clinical trials regarding the alleged adverse effects of MSG. Here, we aim to provide a comprehensive overview of the reported possible risks that may potentially arise following chronic exposure. Preclinical studies have associated MSG administration with cardiotoxicity, hepatotoxicity, neurotoxicity, low‐grade inflammation, metabolic disarray, and premalignant alterations, along with behavioral changes. However, in reviewing the available literature, we detected several methodological flaws, which led us to conclude that these studies have limited relevance for extrapolation to dietary human intake of MSG risk exposure. Clinical trials have focused mainly on MSG effects on food intake and energy expenditure. Besides its well‐known impact on food palatability, MSG enhances salivary secretion and interferes with carbohydrate metabolism, while the impact on satiety and post‐meal recovery of hunger varied in relation to meal composition. Reports on MSG hypersensitivity or links of its use to increased pain sensitivity and atopic dermatitis were found to have little supporting evidence. Many of the reported negative health effects of MSG have little relevance for chronic human exposure and are poorly informative as they are based on excessive dosing that does not meet with levels normally consumed in food products. We conclude that further clinical and epidemiological studies are needed, with an appropriate design, accounting for both added and naturally occurring dietary MSG.

Ameliorative Effect of Graviola (Annona muricata) on Mono Sodium Glutamate-Induced Hepatic Injury in Rats: Antioxidant, Apoptotic, Anti-inflammatory, Lipogenesis Markers, and Histopathological Studies

“…In the intoxicated model, MSG rats, a daily dose of MSG (4 g/kg orally) was given for seven days, which induced kidney injury in rats [9]. According to the last update of the Joint Food and agriculture organization (FAO)/WHO Expert Committee on Food Additives (JECFA), the U.S. Food and Drug Administration (FDA), and the European Food Safety Association (EFSA), the acceptable daily intake of MSG to humans is 30 mg/kg/day [10]. The acceptable daily intake (ADI) is the maximum amount of a chemical that can be ingested daily over a lifetime with no appreciable health risk and is based on the highest intake that does not give rise to observable adverse effects.…”

Knowledge and Awareness of Monosodium Glutamate (Ajinomoto Salt) among Students

“…Many of the reported negative health effects of MSG have little relevance for chronic human exposure and are poorly informative as they are based on excessive dosing that does not meet with levels normally consumed in food products. Hence further clinical and epidemiological studies are needed, with an appropriate design, accounting for both added and naturally occurring dietary MSG [25].…”

Strategies for Reducing Salt and Sugar Intakes in Individuals at Increased Cardiometabolic Risk

“…However, since 1960s, a controversial syndrome, the so-called “Chinese restaurant syndrome” was described as consequence of the use of MSG to flavor most dishes [ 30 ]. However, due to the several methodological flaws, and mixed results of most studies on this topic, there is at present limited evidence for an increased human risk after the intake of MSG [ 31 ]. The use of yeast extract and hydrolyzed vegetable proteins has limitations due to their specific meaty flavor that is not appreciated by all individuals [ 32 ].…”