Have you seen or eaten nutritional yeast?
It’s that cheesy, nutty, flaky, yellow condiment used mainly by vegans and vegetarians to provide protein, minerals, and B vitamins! How couldn’t it be healthy?
A couple of years ago I made a vegan soup for some friends. I added nutritional yeast for a boost of flavor and nutrition, then ate a bowl to double-check the flavors. Within minutes of eating the bowl of soup, I nearly lost both my balance and consciousness.
Several months later, I ate nutritional yeast again and the same symptoms overcame me. The correlation was unmistakable.
I’d been a vegetarian for 10 years and used to eat this seemingly benign and nutrient-infused ingredient! What changed? Who can eat nutritional yeast safely? And who should avoid it?
What Is Nutritional Yeast?
The production of nutritional yeast begins in highly-controlled laboratories, where a common yeast called Saccharomyces cerevisiae grows on one of three nutrient-deficient foods: sugar cane, beet molasses (usually genetically modified), or wood pulp. Lacking an external source of nutrients, the yeast makes its own.
Manufacturers then dry the yeast to preserve its nutrients. They usually spray it with hot gas, a process that causes thermal degradation and loss of nutrients. Nutritional yeast can also be eaten fresh (although this product is no longer available to buy) or dried with a more traditional method called “drum drying”.
Most companies then fortify nutritional yeast by adding vitamins such as folic acid and Vitamin B12. Remember, folic acid is the harmful, synthetic form of folate. Compared with folate, the body does not use folic acid effectively. (Source.)
Only two companies in America (Trim Healthy Mama and Sari) produce both a non-genetically-modified and a non-vitamin-fortified nutritional yeast. Most unsuspecting consumers purchase one of the mainstream brands of genetically-modified, gas-dried, and folic acid-fortified nutritional yeast!
Note: Bob’s Red Mill, Bragg, Frontier, Harmony House, NOW Foods and Red Star nutritional yeast brands all pasteurize their products as well as fortifying with synthetic ingredients (source).
As if that’s not enough, one major issue remains…
Why Nutritional Yeast Is Not Vegan Health Food
The vegan lifestyle means needing to find quality sources of protein due to a lack of animal protein. For many, this means adding nutritional yeast in large quantities to foods and recipes. Commonly referred to as monosodium glutamate (MSG), free glutamic acid is a processed food arguably found in nutritional yeast. In the case of nutritional yeast, manufacturers don’t add MSG intentionally; it occurs because of the manufacturing process. Thus, the misleading wording we often see in the food industry, “no added MSG”, means the product may still contain MSG. (Source.)
Glutamic acid, a naturally occurring neurotransmitter found in plant and animal proteins, excites our taste buds and the neurons in our brains. Whole foods like bone broth and aged cheese contain bound, unprocessed, and healthful (for most people) glutamic acid.
On the other hand, unnaturally fermented or manufactured foods contain something called “processed free glutamic acid”. In other words, glutamic acid has been freed from its protein during the manufacturing process. It is now an excitotoxin.
Excitotoxins interfere with normal brain function by overstimulating neuron receptors in the hypothalamus and causing the death of neurons.
This is why nutritional yeast is considered impure — it most likely contains processed free glutamic acid (source). When ingested, the highly concentrated glutamates enter the bloodstream then the brain without going through the proper channels of digestion (source). 25% of the population reacts adversely to free glutamic acid, usually within 48 hours of ingestion.
The ingestion of MSG has similar side effects to some pharmaceuticals, which can be confusing to consumers (source). Excitotoxins are known to cause long-term, serious neuro-degenerative damage, including Alzheimer’s Disease and Parkinson’s Disease (source).
Are You At Risk?
Truth in Labeling is a website dedicated to exposing the dangers associated with MSG. They list the neurological symptoms I experienced (headache, dizziness, light-headedness, loss of balance) among the common symptoms of MSG. They also record 70 adverse reactions caused by MSG, including cardiac, gastrointestinal and respiratory issues. (Source.)
While MSG does not cause noticeable symptoms in everyone, it is a known carcinogen and damages the brain. More controversial is whether or not nutritional yeast contains MSG. My body’s reaction to nutritional yeast suggests it does. I don’t react negatively to other glutamate-rich foods, like bone broth and aged cheeses (healthful staples in my diet).
“…[S]ome people react to the food ingredient monosodium glutamate. What many don’t know, is that more than 40 different ingredients contain the chemical in monosodium glutamate (processed free glutamic acid) that causes these reactions.” — Jack Samuels, creator of the Truth in Labeling Campaign
Jack Samuels, the late foremost authority on MSG in the traditional community, includes “yeast food, yeast nutrient” in his list of “ingredients that always contain processed free glutamic acid”.
Logically speaking, when we look at how MSG develops in foods, the production method of nutritional yeast matches. It is a manufactured, fermented food, highly concentrated in flavor and glutamates. This kind of man-made food is exactly where we see MSG occurring, as a byproduct of other food processes (source). Also, interestingly, the manufacture of MSG itself is very similar to the process of creating nutritional yeast (source)!
Nutritional yeast is a flavor enhancer! That’s why vegetarians and vegans love it. So is MSG. Any man-made flavor-enhancer should make us cautious.
“Since free glutamic acid is cheap and since its neurotoxic nerve stimulation enhances so wonderfully the flavor of basically bland and tasteless foods, such as many low-fat and vegetarian foods, manufacturers are eager to go on using it and do not want the public to realize any of the problems.” –The American Nutrition Association (source)
Most nutritional yeast is genetically modified and all likely contains MSG, which causes serious neurological disorders and other physiological health problems.
Many consumers are symptom-free, even after years of eating nutritional yeast. However, MSG works slowly and insidiously on the human brain, and it is hard to measure its effects on those who don’t have a glutamate sensitivity.
While nutritional yeast contains amino acids, minerals, and B vitamins, there are better food sources for this nutrition that are not man-made. Babies and children are the most sensitive, and any foods that potentially contain MSG should be strictly avoided (source).
Until we chemically analyze the amount of processed free glutamic acid in different brands of nutritional yeast, we must base our conclusions on the evidence we have. Shall we not eat truly natural, unadulterated, unprocessed, whole foods?
Reasons to Avoid Nutritional Yeast
- Many brands are genetically modified
- Nutritional yeast contains MSG (due to the manufacturing process)
- MSG causes serious neurological disorders
- May experience headache, dizziness, light-headedness, loss of balance
- There are 70 adverse reactions caused by MSG recorded, including cardiac, gastrointestinal and respiratory issues. (Source.)
- You may be symptom free for now, but symptoms can build slowly (bio-accumulation)
- There are better food sources for nutrients found in nutritional yeast (namely amino acids, minerals and B vitamins)
If you still wish to consume even small amounts of nutritional yeast and the MSG does not seem to bother you, Trim Healthy Mama and Sari sell non-genetically-modified, non-fortified nutritional yeast (yes, they probably contain MSG due to the manufacturing process). Avoid other American brands like Red Star nutritional yeast.
What have your experiences been with nutritional yeast?
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