Nutritional yeast (or nooch) may not sound appealing to the typical American, but the English have relied on it for close to a century. Chemists knew of its benefits dating back to the early 1900s (via Britannica). A waste product from brewing, this leftover yeast was manufactured by the English into Marmite to serve as both a nutritional supplement and a spread (e.g., jam). In the 1950s, it started being commercially manufactured as nutritional flakes in the United States.
Its savory, nutty, and cheesy flavor makes it a suitable ingredient for vegan cheese. It can also be sprinkled onto popcorn, added to pasta dishes as a substitute for parmesan cheese, scrambled into eggs, or added to soups for an added “cheesy” flavor and a powerful boost of nutrients. One teaspoon of nutritional yeast is low in calories but a great source of micronutrients, including vitamins B6 and B12 (if fortified), both providing over 200% of your daily value (via Medical News Today). It is also a good source of protein, with all nine essential amino acids, per WebMD.
With that said, nutritional yeast isn’t exactly for everyone. If you have hypertension, glaucoma, or inflammatory bowel disease (IBD), it can worsen your symptoms (via Medical News Today). It’s also not recommended for anyone with risk for gout.