Despite its unappetising name and unappealing appearance, nutritional yeast flakes may be one of the best additions to your diet in terms of nutrition and taste. It provides a wealth of vitamins, minerals and protein that almost anyone—from Paleo enthusiasts to vegans—can enjoy. Don't confuse nutritional yeast with baker's yeast, which is still active and could grow inside your stomach and deprive you of nutrients, or with brewer's yeast, which is inactive but distinctly bitter.What Are Nutritional Yeast Flakes?Nutritional yeast is sourced from whey, blackstrap molasses or wood pulp. “Nutritional yeast is yeast that is grown on molasses or a similar habitat, much like brewer's yeast, a byproduct from producing beer,” says Brandice Lardner, an NASM-certified personal trainer and nutrition coach with One by One Nutrition. “When the yeast is harvested, it is washed and then dried with heat so that it stops growing.” After this heat treatment, it’s crumbled or flaked and packaged for the consumer.