Animal vs Plant Protein

About 20% of the human body is made up of protein.

Because your body doesn't store protein, it's important to get enough from your diet each day.

You can get protein from many food sources, including plants and animals.

Some people claim that the source of the protein, whether animal or plant, shouldn't matter.

Others suggest that plant protein is superior to animal protein.

This article compares animal and plant proteins.

The Amino Acid Profile Varies Between Plant and Animal Proteins

When eaten, protein is broken down into amino acids.

Proteins and amino acids are used for almost every metabolic process in the body.

However, different proteins can vary greatly in the types of amino acids they contain.

While animal proteins tend to contain a good balance of all the amino acids that we need, some plant proteins are low in certain amino acids.

For example, some key plant proteins are often low in methionine, tryptophan, lycine and isoleucine.

BOTTOM LINE:All proteins are made up of amino acids, although the amount and type of each amino acid varies based on the protein source.

Animal Proteins Are Complete, But Plant Proteins Are Not

In total, there are around 20 amino acids that the human body uses to build proteins.

These amino acids are classified as either essential or non-essential.

Your body can produce non-essential amino acids. However, it cannot produce essential amino acids, which need to be obtained through your diet.

For optimal health, your body needs all the essential amino acids in the right ratios.

Animal protein sources, such as meat, fish, poultry, eggs and dairy, are similar to the protein found in your body.

These are considered to be complete sources of protein because they contain all of the essential amino acids that your body needs to function effectively.

On the contrary, plant protein sources, such as beans, lentils and nuts are considered to be incomplete, as they lack one or more of the essential amino acids that your body needs (1Trusted Source).

Some sources report soy protein as complete. However, two essential amino acids are only found in small amounts in soy, so it isn't comparable to animal protein (2Trusted Source).

BOTTOM LINE:Animal foods are the highest quality protein sources. Plant sources lack one or more amino acids, which makes it more difficult to get all the amino acids that your body needs.