Why You Need to Back Away From the Nutritional Yeast

Why You Need to Back Away From the Nutritional Yeast_header


  • Nutritional yeast, or “nooch”, is a dried, inactive form of a yeast called Saccharomyces cerevisiae. It looks like yellow fish flakes, and even though it’s high in B vitamins, it’s definitely not a superfood.
  • Yeasts almost always contain high levels of mold toxins. They also encourage a yeast-like fungus called Candida albicans to grow in your body, which changes the fungal biome of your gut.
  • Gut imbalances cause brain fog, fatigue, food cravings, inflammation, mood changes, weight gain, and even neurological disorders.
  • Lots of dairy-free recipes use nooch to concoct cheese-like sauces. You can do this without the inflammatory yeast by using full-fat coconut milk, butter, ghee, and MCT oil.
  • Instead of nutritional yeast, eat nutrient-dense foods like grass-fed meat and organic dark leafy greens.
  • If you’re vegan, load up on plant-based foods high in B vitamins, like dark leafy greens, almonds, and avocados.


I’m going to piss off tons of vegan and vegetarian readers when I say this, but nutritional yeast (or “nooch”) isn’t good for you.

Sure, it’s packed with vitamin B12, and it’s an ingredient in every vegan “cheese” sauce from here to Timbuktu. However, those yellow flakes that look remarkably like fish food contribute to food cravings, energy lags, and not-so-good fungal changes in your gut biome.

If you feel great when you eat nutritional yeast, more power to you — but if you’re thinking of adding this so-called “superfood” to your diet, then I strongly suggest that you pay close attention to the way it makes you feel. Why? Yeasts almost always contain high levels of toxins that hamper your performance and keep you from feeling your best.

Here’s the lowdown on nutritional yeast and what you should eat instead.

Download this handy guide about what foods to eat and what foods to avoid on the Bulletproof Diet 

What is nutritional yeast?

Bowl and spoon of nutritional yeast

Nutritional yeast is a dried, inactive form of Saccharomyces cerevisiae. That’s the same species of yeast used to brew beer and bake bread. It has a slightly cheesy, umami flavor, and it’s a staple in vegetarian and vegan pantries because it has an impressive nutrient profile. Nooch is naturally packed with B vitamins, which fight off homocysteine — an amino acid which increases brain shrinkage and may lead to Alzheimer’s.[ref url=”https://www.health.harvard.edu/staying-healthy/in_brief_b_vitamins_and_homocysteine”][ref url=”https://www.ncbi.nlm.nih.gov/pubmed/12849121″] 

It’s often hailed as a non-dairy alternative because it dissolves easily in liquid and looks vaguely like cheddar, so you can use it to concoct “cheesy” sauces. I’m all for limiting exposure to the inflammatory proteins and oxidized (aka damaged) fats found in processed dairy, but is nutritional yeast worth the hype? Nope. Here’s why.

Why nooch is a bad idea

Close-up of gut microbes

Your gut is a big deal. When your gut is inflamed or imbalanced, it sends a signal to your brain via the gut-brain axis. Scientists are still investigating the relationship between gut and brain health, but new research echoes what I’ve said for years: What happens in your stomach impacts your mood, stress levels, energy, and weight.[ref url=”https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4662178/”][ref url=”http://advances.sciencemag.org/content/2/1/e1500997″][ref url=”https://www.sciencedirect.com/science/article/pii/S0924933816008464″][ref url=”https://www.nature.com/articles/mp201650″]

As I say in “The Bulletproof Diet,” yeasts almost always contain high levels of mold toxins.[ref url=”https://www.fda.gov/Food/FoodScienceResearch/LaboratoryMethods/ucm2006949.htm”]  After all, they’re fungi. When you eat yeast, it encourages a yeast-like fungus called Candida albicans to grow in your body, which changes the fungal biome of your gut. Here’s why that’s bad news:

  • Toxins from yeast contribute to sugar cravings. Sugar is food for yeast, and studies indicate that gut microbes manipulate your eating behavior so they have more tasty fuel — even at your expense.[ref url=”https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4270213/”]
  • Gut microbiome imbalances contribute to fatigue and brain fog, thanks to cellular damage.[ref url=”https://www.ncbi.nlm.nih.gov/pubmed/7476598″] Those imbalances also cause systemic inflammation.[ref url=”https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4929410/”]
  • A 2016 study found a correlation between Candida and two mental illnesses: bipolar disorder and schizophrenia.[ref url=”https://www.sciencedaily.com/releases/2016/05/160504121327.htm”]
  • Your gut bacteria heavily influence your nutrition. If they’re out of whack, you won’t be able to effectively absorb essential vitamins like vitamin K and and vitamin B12 from your food. Find out how to own your gut bacteria.

Check out this Candida spit test you can do at home tomorrow morning to find out if it’s time to open up a conversation with your doctor about yeast overgrowth. In the meantime, if you want to feel awesome and perform at your peak, avoid all yeasts — including nooch.

What to eat instead of nutritional yeast

"Cheesy" sauce made of butternut squash

Before you do anything else, commit to a healthy gut. Starve the bad yeast and fungi in your system by ditching sugar and eating nutrient-dense foods that actually support a thriving gut microbiome, like what you’ll find on the Bulletproof Diet.

For that cheesy flavor

Spoonful of cheese sauce

OK, nothing can really replicate the flavor of cheese. Some people are able to tolerate raw dairy — if that works for you, enjoy full-fat, organic, grass-fed milk, cream, cheese, and yogurt to reap the anti-inflammatory benefits of omega-3s and a fatty acid called CLA (conjugated linoleic acid). CLA also boosts your immune system, makes you stronger, and may even help prevent cancer.

Or just enjoy a bit more grass-fed butter or ghee with your meal. You’ll get vitamins D, E, and K, beta-carotene, butyrate (an anti-inflammatory fatty acid), and none of the inflammation, brain fog, fatigue, and yeast overgrowth associated with nooch.

If dairy doesn’t agree with you (and it doesn’t for a lot of people) you can replicate the mouthfeel of creamy sauces with full-fat swaps like coconut milk, ghee, butter, and MCT oil.

For B vitamins

Eggs on a dish towel

Nutritional yeast is high in B vitamins — but so are many delicious foods that make you feel great and taste delicious, like grass-fed meat, pastured eggs, and coffee. If you’re vegan, reach for nutrient-packed sources of B vitamins like almonds, dark leafy greens, and avocados. No matter what diet you follow — keto, Paleo, plant-based, or Bulletproof — there are plenty of way more nutrient-dense foods available that won’t wreck your gut flora like yeast will.

For climate change

Broccoli on green background

Do you eat nutritional yeast instead of dairy because you’re swearing off animal products for the planet? Check out this post about why grass-fed beef is the better answer to climate change. Contrary to popular headlines, the answer to climate change isn’t to stop eating meat. Instead, eat organic, grass-fed beef, sourced as locally as possible. If it’s too expensive, eat less of it, and bulk up your plate with organic vegetables, healthy fats, and the occasional sweet potato.

TL;DR: You don’t have to eat yellow flakes just because someone told you that it’s good for your health. If you want to perform at your peak, don’t eat like a fish — eat like your grandma and fill your plate with organic, grass-fed, nutrient-dense whole foods.





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