There are many types of yeast in the world. Some are edible, like active dry yeast used to make bread, and nutritional yeast, the flaky yellow powder you see in vegan recipes. Nutritional yeast has skyrocketed in popularity in the past few years as a vegan cheese substitute, among other applications. Nutritional yeast is a form of deactivated brewer’s yeast and was originally offered as a meat-free source of vitamin B12 and protein for vegetarians and vegans. Now nutritional yeast is commonly fortified with additional vitamins and minerals, like folic acid.

Other types of yeast are inedible, like Candida albicans, the fungus that causes yeast infections. Candida is a type of yeast that normally lives in small amounts in places like your mouth and belly button as well as on your skin. It’s normally harmless, but when the environment is just right, the yeast can multiply and grow out of control. This overgrowth results in an infection called candidiasis.

Nutritional Yeast and Candida

Having some candida on and in your body is completely natural ‒ researchers describe candida as a “normal resident of the human gastrointestinal tract.” Candida thrives in moist environments and can spread very quickly in someone with a weakened immune system as well as in the elderly and the very young. Candida can cause things like yeast infections, thrush (called oral candidiasis), and diaper rash (cutaneous candidiasis). In some cases, candida can make its way into your bloodstream and cause a serious, life-threatening infection.

So is eating a form of yeast while you have candidiasis safe? You might assume that eating nutritional yeast when you have an overgrowth of candida isn’t advisable. “Not so,” says Vanessa Clermont, registered dietitian and Integrative Nutrition Health Coach. “Candida grows in the presence of sugars in food and stems from an overgrowth of the yeast already in the body,” she explains. “Nutritional yeast does not cause yeast infections or candida overgrowth because of the elimination of yeast cells during processing. Essentially, the yeast that causes infections isn't present.”

Benefits of Nutritional Yeast

Nutritional yeast is a versatile food that works with nearly every type of diet. It’s low in sodium and calories; is fat-, sugar-, and gluten-free; and is vegan.

One serving (around two tablespoons) of nutritional yeast contains:

• 45 calories
• 8 grams of protein
• 1 gram of fat
• 5 grams of carbohydrates
• 4 grams of fiber
• 6 milligrams of thiamin (640% recommended dietary intake [RDI])
• 7 milligrams of riboflavin (570% RDI)
• 56 milligrams of niacin (280% RDI)
• 6 milligrams of vitamin B6 (480% RDI)
• 8 micrograms of vitamin B12 (130% RDI)

It’s a complete source of protein

Nutritional yeast contains all nine essential amino acids that we need to get from our diet, making it a complete source of protein, similar to the protein found in animal products. Complete proteins assist in repairing tissues, absorbing nutrients, and preventing muscle loss.

It’s good for heart health

Nutritional yeast contains special fibers called beta-glucans, which have been shown to reduce cholesterol levels. Nutritional yeast can also help regulate blood sugar levels, as it’s a low-glycemic food. Plus it contains chromium, a mineral that can also help regulate blood sugar.

It prevents vitamin B12 deficiency

Nutritional yeast is very high in vitamin B12, which is needed for a healthy nervous system, DNA production, energy metabolism, and creation of red blood cells. It’s usually found in animal proteins, which makes nutritional yeast a great way for vegans and vegetarians to supplement their vitamin B12 intake.

It’s high in antioxidants

Antioxidants fight free radicals in your body, which can cause illnesses, spark inflammation, and contribute to the effects of aging. Nutritional yeast contains glutathione, a powerful antioxidant that can help protect your body from the effects of free radicals.

Are There Downsides to Nutritional Yeast?

As with most foods, there are some potential downsides and side effects to consuming nutritional yeast. If you have a yeast intolerance, it’s best to avoid nutritional yeast altogether, says Clermont. Additionally, some people with inflammatory bowel disease (IBD) find that nutritional yeast triggers flare-ups of their IBD symptoms. It’s thought that yeast can trigger an immune response; people with IBD have overactive immune systems that attack their digestive systems.

It can cause digestion problems

Because nutritional yeast is so high in fiber, introducing it into your diet in large quantities can lead to gastrointestinal distress. Fiber is great for keeping you regular, but it’s important to slowly introduce fiber to your diet, especially if you don’t typically eat fiber-heavy foods.

It may trigger headaches

Yeast products like nutritional yeast contain tyramine, a compound derived from the amino acid tyrosine. While rare, people find that tyramine can cause migraine headaches. More research is needed to determine why this happens, but it’s believed tyramine interacts with the central nervous system, releasing hormones that lead to an increase in blood pressure, resulting in headaches.

It can cause flushed skin

Nutritional yeast is an excellent source of vitamin B3 (also known as niacin), but large amounts of the vitamin can cause facial flushing, an uncomfortable reddening of the face that may include itching and burning. Very high amounts of B3 can also cause liver failure.

The Bottom Line

Nutritional yeast boasts a heap of nutritional benefits, particularly if you’re following a plant-based, vegan, or vegetarian diet. It’s high protein content and nutty, cheesy flavor also make it a great addition to all diets.

Although it is a form of yeast, nutritional yeast won’t make bread rise. Since it’s deactivated, the yeast cells are not alive and won’t contribute to candida growth on your body. If you’re getting candidiasis infections regularly, it’s best to talk with your doctor about the cause and treatment. Ask if eating nutritional yeast works for your situation.