Plant-Based Proteins Are Complete

There’s a lot of talk about how people can get all nine of their essential amino acids on a plant-based diet.

Much of this discourse centers around which plant-based protein sources are “complete” and “incomplete” - meaning which ones contain all nine essential amino acids, and which ones lack some of these.

So I conducted a meta-analysis of scientifically peer-reviewed studies in order to analyze the protein content, amino acid profile, and nutritional makeup of the most common plant-based protein sources - both foods and supplements.

You can find my full methodology at the bottom of the page.

Key Findings

• The idea that most plant-based proteins are “incomplete” is simply not true. 14 of the 17 most popular plant-based protein sources contain all nine essential amino acids.


• Lentils are the best plant-based protein source for muscle growth. Lentils contain more of the three most important amino acids for building muscle (leucine, methionine, and valine) per portion than any other protein source.


• We’d recommend eating a portion of lentils or pumpkin seeds every day because of their methionine content. Methionine is the hardest amino acid to get from a plant-based diet.

The Amino Acids in Plant-Based Protein

The tables below show the percentage of daily requirements of the nine essential amino acids in a portion of 17 popular plant-based protein sources.

Protein Content in Typical Servings

Please note that these findings are based on the typical serving size of each foodstuff taken from Verywell Fit’s website.

This is how much protein a typical serving of each foodstuff contains:

The Amino Acids in Plant Based Protein Powders

I also put together the quantity of amino acids found in the twelve most common protein sources used in plant-based protein powder.

Key Findings

• Brown rice protein powder is the best protein supplement for building muscle as it contains the most leucine, lysine, and valine, the three amino acids most involved in building muscle.
• Pumpkin seed and sacha inchi protein powder are the best sources of methionine, the hardest amino acid to find in a plant-based diet.
• Lentil proteinis the best protein supplement for older people as it contains by far the most threonine, which is essential for maintaining connective tissue.
• Sacha inchi is the best plant-based protein supplement for improving mood and cognition as it contains the highest amounts of phenylalanine and tryptophan, which contribute to the creation and maintenance of neurotransmitters.

Amino Acid Content in One Scoop of Plant-Based Protein Powder

The table below shows the amount of amino acids found in one scoop of plant-based protein powder. This data assumes that one scoop of protein powder contains 20 grams of protein.

Note: Sunflower seed protein powder and mung bean protein powder are the only incomplete proteins in this list. If you are buying these protein powders, you might want to consider blending them with other protein supplements.

Percentage of a Man’s Daily Amino Acid Requirements in One Scoop of Protein Powder

Percentage of a Woman’s Daily Amino Acid Requirements in One Scoop of Protein Powder

What Do the Different Amino Acids Do?

The table below describes how each of the nine essential amino acids contribute to our functioning:

Methodology

We went through 19 papers published in the National Library of Medicine to find the amino acid composition of the 19 most popular vegan sources of protein. These were all measured in terms of milligrams per gram of protein (mg/g).

To determine the amino acid content in foods, we:

• Multiplied the mg/g value by the amount of protein found in a typical serving.
• Used the VeryWell Fit to find standard serving sizes.
• Divided by the daily amino acid requirement for men and women as per Cleveland Clinic.

For the amino acid content in protein supplements, we:

• Multiplied the mg/g of amino acid by **20** (since a scoop of protein powder typically contains 20g of protein).
• Divided this value by the daily amino acid requirements for men and women as per Cleveland Clinic.

You can find the quantity of amino acids in each protein source (measured in mg/g) in the table below, along with the journal source where they were found.

Amino Acid Content Per Gram of Protein (Source Material Hyperlinked)