Vegan protein refers to any food rich in protein that does not come from an animal or animal product, and that does not contain any animal protein. As humans require roughly 10-15 percent of their daily calories to come from protein, it is an essential nutrient in the diet. Of the 20 amino acids the body requires from protein, however, only 11 can be manufactured by the body. The remaining nine must be obtained through the diet and therefore are referred to as the essential amino acids. Though these are more readily available in animal foods, a vegan diet can supply enough of the essential amino acids, provided that a variety of foods are consumed.
Along with carbohydrates and fat, protein is one of the three macronutrients, or nutrients, in the diet that supply calories. This nutrient, vegan protein included, plays many important roles in the body, including repairing and building body tissues such as bone and muscle, metabolizing cells, transporting oxygen throughout the body, and manufacturing more amino acids. Amino acids are referred to as “the building blocks of protein,” as protein is made up of chains of individual amino acids. Different foods supply different combinations of amino acids, and foods containing most or all of the essential amino acids are known as high-quality or complete proteins, whereas those that are missing some of the essential amino acids are known as low quality or incomplete proteins.
One controversy surrounding the vegan diet is whether enough amino acids can be obtained through plant foods, as vegan protein is typically classified as an incomplete protein source while animal protein is labeled a complete protein source. Nutrition experts tend to recommend ingesting a mixture of complete and incomplete proteins throughout the day to ensure enough of the essential amino acids are consumed. Vegans can meet their needs, however, by eating a variety of foods rich in vegan protein, foods such as soybeans, lentils, black beans, peas, almonds, and peanut butter. Many of these foods contain almost all of the essential amino acids, though one food might be high in one amino acid like leucine and low in another like tryptophan. By eating a mixture of protein-dense food throughout the day, one can overcome amino acid deficiencies in any individual food.
As long as ten percent of a person's daily calories come from protein, vegans generally can obtain all the nutrition they need through plant foods. Alternately, protein needs can be calculated by aiming for 0.8 to 1 gram of vegan protein per kilogram (0.35 to 0.45 grams per pound) of body weight. Athletes or anyone who lifts weights may require additional protein and should consult a nutrition expert.