MSG, or monosodium glutamate, is one of the most commonly used food additives to enhance the flavors of food, especially in Asian cuisine and processed products. 

Monosodium glutamate is the sodium salt of glutamic acid, a non-essential natural amino acid found in nearly all foods. It is especially present in protein-rich foods such as dairy products, meat, fish, and many vegetables. Additionally, some foods frequently used to enhance flavors, like mushrooms and tomatoes, have high levels of natural glutamate. 

In 1908, during a dinner, biochemist Dr. Kikunae Ikeda (one of the future founders of Ajinomoto) wondered what gave his soup its delicious flavor. His wife suggested it was the Kombu seaweed. Inspired, Dr. Ikeda extracted a crystalline compound from the Kombu broth, which turned out to be glutamic acid. This compound had a unique savory taste that he named umami, based on the Japanese word umai (delicious), and patented monosodium glutamate (MSG) to reproduce this flavor.

In 1909, Ajinomoto Group was founded and launched MSG in Japan. Initially, MSG was derived from wheat gluten. In the 1930s, it began to be extracted from soybeans, and in the 1960s, production was modernized using bacterial fermentation of sugarcane.

So, if we say that glutamate is a natural compound present in many ingredients, what about the controversial monosodium glutamate?

Natural glutamate is part of the proteins in those foods and is bound to other molecules. It is not a free compound, and in its natural form, it contributes to the umami (savory) flavor of foods and also performs biological functions in the body. Monosodium glutamate, on the other hand, is an ultra-processed form of glutamate produced industrially. It is more concentrated than natural glutamate and is added directly to foods.

This food additive is known for causing "Chinese restaurant syndrome," which causes headaches, anxiety, and a range of symptoms that were once thought to be an allergic reaction or hypersensitivity to this compound. However, there is increasing evidence confirming that MSG has much deeper implications for our health.

Several studies have revealed that MSG has a toxic effect on fetal development, in children, adolescents, and adults. Physiological complications associated with MSG toxicity include hypertension, obesity, gastrointestinal issues, and deterioration of brain function, the nervous system, the reproductive system, and the endocrine system. The effect of MSG depends on its dosage, the route of administration, and the exposure time; and today we are much more exposed to consuming large amounts of additives, including MSG,  even without realizing it.

In one study, researchers used MSG to create a model in mice that mimics obesity and glucose-related issues such as type 2 diabetes. When mice are exposed to MSG, they become obese and develop problems with blood sugar and insulin. Additionally, their body fat produces more inflammatory substances, which may explain why obesity is often associated with inflammation. They also found that MSG caused significant alterations in the structure of the liver and heart of these mice. There was an imbalance in blood lipid levels, known as dyslipidemia; enzymatic markers indicated toxicity in both the liver and heart, and the redox state (balance between oxidants and antioxidants) was altered, suggesting oxidative stress.

Another study shows how MSG might affect the placenta during pregnancy. The placenta is crucial because it nourishes the developing baby. Scientists found that MSG increases the production of harmful substances called "reactive oxygen species" (ROS) in placenta cells. These substances can damage cells and disrupt important functions such as growth and implantation of the placenta in the uterus. If the placenta does not function properly, it could affect the baby. It was also observed that MSG causes stress in critical parts of the cell, which could worsen the problem, leading to negative effects on both maternal and fetal health.

In summary, these studies suggest that MSG may have many negative effects on our health, affecting how the body handles sugar, causing inflammation, cellular damage, and more.

Monosodium glutamate (MSG) can appear on product labels under various different names. Here are some of the most common:

• Monosodium glutamate (E621)
• Monopotassium glutamate (E622)
• Calcium glutamate (E623)
• Monoammonium glutamate (E624)
• Magnesium glutamate (E625)
• Natrium glutamate
• Sodium glutamate
• Hydrolyzed sodium glutamate
• Glutamate salt
• Sodium caseinate
• Sodium glutamate
• Glutamic acid (E620)
• MSG
• Ajinomoto
• Umami flavoring
• Hydrolyzed vegetable protein (often contains MSG)
• Yeast extract (sometimes contains MSG)
• Soy protein extract (may contain MSG)
• Powdered seasoning (may include MSG)
• Protein flavoring (may contain MSG)
• Artificial or natural flavoring
• Glutamate flavoring
• Hydrolyzed wheat protein (may contain MSG)
• Flavor enhancer
• Hydrolyzed protein

It is important not only to read the labels of each product you buy but also to ask the staff at restaurants where you eat to find out if they add MSG to their dishes. Nowadays, we cannot trust the food industry or assume that all restaurants use genuine and healthy ingredients. We need to ask questions, scrutinize everything, investigate, and demand what our bodies need to function properly. Remember, when in doubt about something, think that the answer will always be in what nature provides us in its purest state; everything else will always be in question.