Nutritional yeast (saccharomyces cerevisiae) is a non-active yeast that is derived from either cordyceps or molasses. Not to be confused with brewer’s or baker’s yeast, this yeast is, in its simplest description, a wonderful source of vitamin B that adds a little bit of “cheesy” flavor to whatever it is added to. In fact, nutritional yeast is such a good source of the Vitamin B complex that vegans use this food as a supplement to increase the vitamins that are usually found in animal products. In essence, nutritional yeast is a Vitamin B complex.
In contrast, MSG (monosodium glutamate) is the sodium salt of glutamic acid. It is a flavor enhancer that is part acid, part sodium and has no nutritional benefit.
There has been confusion about nutritional yeast either being MSG or containing MSG due to the existence of glutamic acid in both.
(Quick note: Glutamic acid and glutamate are essentially synonymous. The largest difference is how the body responds. To keep it simple, glutamic acid enters the body and the body naturally "drops" the oxygen molecule, making it glutamate. For this article, we use the terms interchangeably).
The difference between the two is that MSG is a concentrated source of this naturally occurring compound that also includes sodium. In addition, many yeast extracts have added MSG. Nutritional Yeast is not a yeast “extract”, rather, it is an inactivated, whole yeast product and is not identical to MSG either practically or chemically.
In fact, studies have shown that “Glutamate is naturally produced in human bodies and also exists in many of the foods we eat such as Parmesan cheese, tomatoes, mushrooms, walnuts, eggs, chicken, beef, pork, carrots, peas and other vegetables… Glutamate is also produced in the body and plays an essential role in human metabolism.” (1) Glutamate been proven to improve digestion, particularly in the gestation period, and continues to benefit growth due to its ability to support protein formation – an action that is essential to organic life (4).
However, despite the research done on this fascinating compound, there still lies the specific confusion that nutritional yeast is, in fact and whole, MSG. If we break down the acronym back to its meaning, we have first and foremost the description of monosodium. This is what differentiates MSG from nutritional yeast, in that, “MSG… is the isolated sodium salt of glutamic acid, which is a synthetically created compound used to enhance the flavor of processed foods. Both naturally occurring glutamate and MSG contain glutamic acid, but the compounds behave differently in the body.” (2) (Emphasis added)
To further clarify, “Glutamic acid found in unadulterated protein does not cause adverse reactions. To cause adverse reactions, the glutamic acid must have been processed/manufactured or come from protein that has been fermented.” (3) In our products, we use the Red Star Nutritional Yeast which is Certified GMO Free and contains no added MSG. It is unprocessed in the chemical sense, meaning that it is “harvested” rather than chemically processed. Think of collecting mushrooms versus laboratory modification – this is nearly an exact analogy. We also use this product conservatively, as to not overwhelm the flavor of our food products but rather contribute a “cheesy” flavor to our plant-based products that do not contain cheese.
In conclusion, both ingredients (MSG and Nutritional Yeast) contain glutamate but the difference is in the process and the concentration of sodium. Nutritional Yeast contains a very minimal and naturally occurring amount of glutamic acid. MSG, in essence, is the harmful condensation of both glutamic acid and sodium. While glutamic acid is in MSG, glutamic acid, or glutamate, does not equal MSG. We believe that part of the confusion between MSG and Nutritional Yeast comes from low-quality Nutritional Yeast products having either added or enhanced glutamic acid. Red Star Nutritional Yeast does not practice this process, which is why we chose this particular brand.
In rare cases, there are reports of individuals being particularly sensitive to the amino acid of glutamate, however more commonly in high doses. Always refer to your doctor before adding any food or supplement to your diet.