Vegetarian diets are among the most popular diets around the world. People follow vegetarian diets for many reasons, like health, religion, and economics. Based on the Healthy Eating Index (HEI)-2015 scores, the overall diet quality of vegetarians with health-related motives is higher than those of other motives. However, there is a controversy among studies about the effectiveness of vegetarian diets in achieving protein and amino acid adequacy for both adults and vulnerable groups (such as the elderly and children) who suffer from protein deficiency problems because vegetarian diets limit the consumption of meat and/or animal derivatives (depending on the type of diet) which are generally known as the primary sources of protein. For this reason, it was necessary to study the importance of adequate protein consumption in vegetarian diets in terms of both quantity and quality. The quality of proteins is evaluated based on their digestibility and bioavailability. One method used to determine dietary protein quality that reflects the true ileal digestibility of amino acids and computes protein availability in diets is the Digestible Indispensable Amino Acid Score (DIAAS). These scores indicate that plant-based protein sources are low in bioavailability, therefore plant protein consumption may need to be increased or combined to improve the biological value of protein intake and maintain bone health and lean mass. In summary, a vegetarian diet can be beneficial in the long term if it is well-planned. (ORCID ID: 0000-0001-6876-577X)

Anahtar Kelimeler: Vegetarian diet, Vegetarianism, Nutrition, Protein, Plant Protein, Amino acids