Final answer:
Essential amino acids must be consumed through diet as the body cannot produce them, whereas non-essential amino acids can be synthesized by the body. Vegan and vegetarian diets often require careful planning to ensure all essential amino acids are obtained, as plant proteins may not provide all of them in comparison to animal proteins.
Step-by-step explanation:
The distinction between essential and non-essential amino acids is crucial for individuals following a vegetarian or vegan diet. Essential amino acids are those that the human body cannot synthesize on its own and therefore must be obtained from the diet. These include phenylalanine, valine, threonine, tryptophan, methionine, leucine, isoleucine, lysine, and histidine. In contrast, non-essential amino acids are those that the body can produce and do not need to be consumed through food.
Vegans and vegetarians need to pay special attention to the protein they eat because plant proteins are often incomplete, meaning they may be lacking in one or more essential amino acids. Consequently, it is important for those on a plant-based diet to consume a variety of plant sources to ensure that all essential amino acids are obtained. While animal proteins typically contain all nine essential amino acids, those following plant-based diets can still meet their nutritional needs through careful dietary planning.