We all used to eat on Chinese restaurants and go to dinner in hotels on weekends frequently. Again we use many packaged foods and drinks which may contain high level of preservatives, also harmful substances like arsenic, mercury and pesticides found in some foods. Now we are facing many health issues, mainly in young generations and children.
Monosodium glutamate (MSG) is a flavor enhancer often added to restaurant foods, canned vegetables, soups, deli meats and other foods. The U.S. Food and Drug Administration (FDA) has classified MSG as a food ingredient that’s generally recognized as safe..Despite a small number of persons reporting sensitivity to MSG, scientific studies have not shown any direct link between MSG and adverse reactions in humans. MSG used to be blamed for the “Chinese Restaurant Syndrome” because the first anecdotal report was made following consumption of a Chinese meal. Symptoms said to be experienced included burning sensations along the back of the neck, chest tightness, nausea and sweating. However, a double-blind controlled challenge of individuals claiming to suffer from the “syndrome” failed to confirm MSG as the causative agent. Other studies have found that allergic-type reactions after Asian meals are more often due to other ingredients such as shrimp, peanuts, spices, and herbs. If you think you are sensitive to MSG or any other food ingredient, the best advice is to check with your doctor or with a dietitian. MSG has also been reported to cause all sorts of modern diseases and symptoms, from (migraine) headaches to asthma, overweight, and even cancer. However, current evidence does not support these statements. There have been many studies conducted investigating the relationship between MSG and (migraine) headaches, however, a causal relationship between the two has yet to be established. Alongside, there has not been a definitive answer as to whether MSG can serve as a trigger for asthma since previous studies exploring this relationship had improper study methods.3,8 Regarding overweight, while animal studies have shown increases in body weight following MSG injections (mainly in extremely high doses), data from human studies have shown equivocal results. Some research suggests that MSG may suppress appetite, while others suggest that its flavour-enhancing effects may lead to overeating.2 Lastly, even with the highest doses tested, no increased tumour rates were found following MSG consumption.
According to several health authorities, including the Joint FAO/WHO Expert Committee on Food Additives (JECFA), the Food and Drug Administration (FDA), and the European Food Safety Authority (EFSA), MSG is generally considered to be safe.2,3 The acceptable daily intake (ADI) for MSG is set at 30 mg/kg of body weight per day, which is significantly more than you would normally consume on a regular basis.
A study on a human model revealed that MSG consumption and hemoglobin levels are positively related to each other due to leptin’s vital role in haematopoiesis (Shi et al., 2012[15]). Other studies have indicated however that beside MSG’s stimulation, there might be other mechanisms which disrupt normal physiological function of hematologists. Further research should be carried out to explore the relationship between nutritional intake of MSG and suchlike physiological mechanisms. A promising recent discovery indicates that α-ketoglutarate dehydrogenase, glutamate receptors and cysteine-glutamate anti porters have a potential role in up regulation of oxidative stress in MSG-inducted toxicity (Sharma, 2015[14]).
The harmful effects of MSG described in this paper might be perceived only by a small number of scientists, but they represent a silent threat posed by the consumption of this popular additive to all of society. It has been suggested that toxicity of MSG can be overcome by the use of certain kinds of vitamin like A, C, D and E. Quercetin and diltiazem have also been suggested to play a protective role in MSG-induced toxicity (Mustafa et al., 2017[11]). Vitamin A and C have been shown to protect nerve cells and cerebral cortex in male albino rat models. The supplementation of vitamin D and E in MSG-induced oxidative stress led to decreased lipid peroxidation, catalase and superoxide dismutase in the liver. It also improved levels of glutathione. Quercetin has been proven to reduce glucose, leptine and creatinine levels, which in turn enhances superoxide dismutase and glutathione peroxidase, while diltiazem protects against morphological functional disorders. Furthermore, new research explores the function of curcumin in the amelioration of cognitive damage via stabilisation of acetyl cholinesterase (AchE) levels and reduction of TNF-α. Furthermore, curcumin acts as a protective agent against neural damage due to its effect of decreasing the expression of mGLUR5 and N-Methyl-D-aspartate receptors 2B (NMDA2B) in the hippocampus. Because of its properties that help balance glutamate levels scientists have suggested the introduction of combinations of curcumin and MSG in the market .
In conclusion we would like to state that although MSG has proven its value as an enhancer of flavour, different studies have hinted at possible toxic effects related to this popular food-additive. These toxic effects include CNS disorder, obesity, disruptions in adipose tissue physiology, hepatic damage, CRS and reproductive malfunctions. These threats might have hitherto been underestimated. In the meantime, people keep using ever larger amounts of MSG unaware of the possible consequences. Further studies need to be undertaken in order to assess the connection between MSG and cardiovascular disorders, headache, and hypertension in human models. MSG is a controversial food-additive used in canned food, crackers, meat, salad dressings, frozen dinners and a myriad of other products. It is found in local supermarkets, restaurants and school cafeterias alike. While MSG probably has huge benefits to the food industry, the ubiquitous use of this food-additive could have negative consequences for public health. If more substantive evidence of MSG-toxicity would be provided, a total ban on the use of MSG as a flavor enhancer would not be unwise to consider.