Which statement best describes incomplete proteins?

Which statement best describes incomplete proteins?

• A. They lack one or more essential amino acids
• B. They provide all essential amino acids
• C. They are only found in animal foods
• D. They are always paired to form complete proteins

Answer: (A)

Incomplete proteins are those that do not supply all of the essential amino acids in the amounts the body needs. Essential amino acids must come from the diet, and many plant-based proteins are lacking in one or more of these building blocks. Because of this, you typically need a variety of protein sources to meet daily amino acid needs, rather than relying on a single source. The idea that plant proteins are always paired in the same meal is a common teaching, but it’s enough to eat different protein foods across the day to achieve a complete amino acid profile. So, the statement that best describes incomplete proteins is that they lack one or more essential amino acids.

Incomplete proteins are those that do not supply all of the essential amino acids in the amounts the body needs. Essential amino acids must come from the diet, and many plant-based proteins are lacking in one or more of these building blocks. Because of this, you typically need a variety of protein sources to meet daily amino acid needs, rather than relying on a single source. The idea that plant proteins are always paired in the same meal is a common teaching, but it’s enough to eat different protein foods across the day to achieve a complete amino acid profile.

So, the statement that best describes incomplete proteins is that they lack one or more essential amino acids.