What’s So “Nutritional” About Nutritional Yeast?

These funky flakes might be the OG health food fad.
Flakes of Bragg's nutritional yeast.
Photo by Travis Rainey, Styling by Joseph De Leo

All products featured on Epicurious are independently selected by our editors. However, when you buy something through our retail links, we may earn an affiliate commission.

Long used as a cheese substitute, nutritional yeast is beloved by vegetarians and vegans looking to add umami to their meals. But it’s not just for veg-heads. The savory seasoning brings a cheesy, almost nutty flavor to just about any dish: popcorn, pasta, salad dressing, you name it. Even if nutritional yeast is already a countertop mainstay in your household, you might have some questions about what it’s actually made of—after all, the large yellow flakes look suspiciously similar to fish food. If you’ve ever stared at that yellow shaker bottle on your counter and wondered, What is nutritional yeast, really? we’ve got answers.

What actually is nutritional yeast?

Nutritional yeast (nickname “nooch”) is a dried, deactivated form of Saccharomyces cerevisiae, an ancient species of yeast. Like baker’s yeast—and the hundreds of types of yeast that exist all around us—nutritional yeast starts as wild yeast, which grows naturally on cane or beet molasses. The yeast is picked, rinsed, and heat-dried to destroy any live cultures, thus deactivating the yeast and stripping it of its leavening properties. Brewer’s yeast—a by-product of beer-brewing—is similarly inactive, rendered so by rising alcohol levels and pasteurization. Though both nutritional and brewer’s yeast descend from the same fungus as baker’s yeast (often sold as either fresh cake yeast or active dry or instant yeast pellets), these deactivated types of yeast cannot be used as a leavening agent in bread or pastries.

Image may contain: Food, Mustard, and Ketchup

Bragg Premium Nutritional Yeast Seasoning, 4.5 oz (Pack of 2)

What’s so nutritional about it?

In the 19th century, a German scientist named Justus von Liebig made a discovery that would shape British foodways and their diaspora forever: He found that the yeasty by-product of beer brewing (a.k.a. brewer’s yeast) could be harvested and compressed into a flavor concentrate that resembled meat but was completely vegetarian. In 1902 the Marmite Food Company launched its signature product: a dark, savory spread made from yeast extract.

Brewer’s yeast may very well have been the first health food fad. In 1916, around 5 years after the advent of the term vitamin, chemist Atherton Seidell published an article on the potential to use brewer’s yeast as a cheap supply of nutrients, NPR reports. Seidell’s experiment involved feeding filtered brewer’s yeast to paralyzed pigeons; he found that “a relief of the paralysis occurred within an hour,” though he acknowledged that a dose would have to be much more concentrated to have significant effects on humans. Still, Seidell deemed yeast an affordable potential treatment for “nutritional deficiency diseases,” like beriberi and pellagra.

A 1952 advertisement from a British magazine espousing the benefits of yeast tablets.

M&N / Alamy Stock Photo

As the concept of the vitamin gained steam, Marmite—considered a “great source of five important ‘B’ Vitamins,” the brand writes—gained the tagline of “nutritious.” The savory spread was packed in troops’ rations during the first World War. Soon enough American companies got in on the action. A 1920s ad for Fleischmann’s Yeast Co espoused “yeast for health,” linking the company’s fresh yeast cakes to a slew of benefits, Catherine Price explains in an article for the Science History Institute: “Yeast was good for skin troubles, stomach troubles, and a ‘general run-down condition’; Eat a cake before every meal—but be patient: results, the ads emphasized, might take months to see.” In 1944, the yeast cake party got a reality check. The Federal Trade Commission charged Standard Brands (Fleischmann’s parent company) with “falsely advertising the therapeutic properties of Fleischmann's Compressed Yeast,” the New York Times reports.

Still, the idea of yeast as “nutritional” remained embedded in public consciousness, and companies sought to tread further into the health foods frontier. Brewer’s yeast—the key ingredient in Marmite—had a strong, bitter taste, so producers sought to cultivate a more palatable variety of dried yeast specifically as a supplement. In 1950, Red Star produced the first nutritional yeast by heat-drying (and therefore deactivating) a type of yeast that grew on glucose. As compared to products made from brewer’s yeast, the resulting yellow flakes had a still-savory, yet mild flavor; some might recognize Marmite’s distinct funk in the product’s lineage.

Nope, those funky flakes aren’t fish food.

Photo by Travis Rainey, Styling by Joseph De Leo

Nutritional yeast gained real traction during the vegetarian boom of the 1960s and ‘70s, when it was marketed as a good, meat-free source of protein and vitamin B12. But unlike yeast supplements of years past, it also tasted really, really good. Like apple cider vinegar, nutritional yeast became the object of a devoted fan base, particularly popular among those following a plant-based diet. But in recent years, the cult-favorite seasoning has swum into the mainstream: Sales of nutritional yeast in the US increased 20% between 2019 and 2020, as reported by the New York Times.

Today Bragg advertises its nutritional yeast as a “good source of complete protein,” with five grams of protein per two-tablespoon serving, also touting it as “packed with” thiamin, riboflavin, niacin, folic acid, and vitamins B6 and B12. Unfortified nutritional yeast does not naturally contain vitamin B12, so some producers fortify the yeast by introducing extra vitamins (typically B12) to the mix. It’s hard to say whether most consumers are compelled to buy the stuff for its alleged health benefits, or simply because it tastes good.

What is nutritional yeast used for?

Like salt or MSG, a pinch of nutritional yeast adds nutty, deeply savory flavor to countless dishes—and you can use it the same way you would any spice in the cabinet. “My number one key ingredient for adding umami to any dish or recipe is nutritional yeast,” says Timothy Pakron, author of Mississippi Vegan. “Because it is high in glutamic acid, it has naturally occurring umami. This heightens the flavor of everything—roasted vegetables, soup, stews, gravies, sauces, grains, and bread.” Andrea Nguyen, author of Vietnamese Food Any Day, offers nutritional yeast as a swap for MSG in her recipe for buttery Umami Garlic Noodles With Mustard Greens

There are no wheat or animal products used in its production, so nutritional yeast is completely gluten-free and vegan. A substantial amount of the seasoning—like the ¼ cup in this vegan beer-cheese sauce—will bring a strong, distinctly cheesy note, but a little can go a long way towards building flavor. Pakron often uses a small amount of nutritional yeast flakes in his recipes—enough to bring a boost of umami, but not so much that it adds a discernible flavor. 

Particularly popular in vegan recipes, it brings an unmistakably cheesy flavor to our Easy Vegan Mac and Cheese and the “cheese” sauce in vegan cheesesteaks. Associate food editor Kendra Vaculin uses it to replace Parmesan cheese in her best vegan pesto, where the flavorful flakes—which she dubs “the prototypical cheese flavor alternative”—offer funk and cheesy tang. “In many recipes, you’ll find it used as a one-for-one swap for the grated cheese, with everything else in the formula staying the same,” Kendra writes. 

You can find nutritional yeast—Bragg and Bob’s Red Mill are popular brands—at most grocery stores, health food stores, and online. Whether you eat dairy or not, it’ll punch up your tofu scramble, your ranch fun dip, or your next bowl of popcorn.