What Are ‘Complete’ Proteins?

What Are ‘Complete’ Proteins?

There is a lot of assumed knowledge in the world of health and fitness, and a phrase that gets thrown around a lot is ‘complete protein’. But what exactly is a complete protein? And how can you get more into your diet?

Before we get too ahead of ourselves, let’s keep it basic and look at what protein is. A protein is a macronutrient made up of amino acids. There are 20 amino acids which each have their own impact on important functions. Proteins contain these in abundance and have been shown to improve muscle growth, muscle mass, and muscle maintenance. This is mainly done through the amino acid Leucine. 

What is Protein?

Sources of protein vary but the many types are milk, meat, and plant based protein. Protein has gained popularity in health and fitness thanks to its ability to aid muscle development and improve all around health.

What is a ‘Complete’ Protein?

The definition of a complete protein revolves around those all important amino acids. As already mentioned there are 20 amino acids in total, with nine of those being essential amino acids. The nine essential amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.

Complete proteins contain a sufficient amount of all nine of the essential amino acids to be regarded ‘complete’. Any which don’t are regarded as an incomplete protein. Leucine is the key essential amino acid for building muscles and any foods which contain a high amount of leucine will be great for muscle building. If you’re finding it tough to get complete proteins into your diet try powders or bars, which should contain over 15 grams of protein each serving as a minimum.

Vegan Sources of Complete Protein

Finding complete protein in animal products is pretty easy, so as long as meat eaters are eating healthy enough they should consume enough. For those on vegetarian diets or plant based diets, finding complete proteins can be a bit tougher.

It was originally thought that vegetarians and vegans could only get seven of the nine essential amino acids through their diet. It has since been shown that in mixing foods during the day it is quite easy to hit all nine essential amino acids in a high enough quantity.

There are a wide variety of good sources of complete protein in plant based foods. Here is a quick list of nine sources of complete protein for vegan diets:

Chia Seeds

Chia seeds are packed full of iron, calcium, zinc, and antioxidants. They are perfect to have on their own or add them to some of your recipes for a complete protein kick.

Peanut Butter

High protein content, plus super tasty. What isn’t there to love about peanut butter. Spread this on toast or a bagel for a great snack


Buckwheat is an imposter. Well in the sense that it isn’t even a type of wheat at all. It’s actually from the same family tree as rhubarb. Japanese buckwheat noodles, or soba as they are more commonly known, are super tasty and teeming with plant proteins. 

Hummus and Pita

Hummus and Pita is a great go-to snack. A classic combination that is timeless. Tasty, healthy, and even better now you know it is a complete protein!


I think I may be the biggest quinoa advocate in the world. This ancient grain is a superfood that has been popular across the world for generations. Perfect as part of a meal or as a snack on its own!


Considered a superfood, spirulina isn’t a complete protein on its own but add some oats, grains, nuts or seeds and you’ll hit all those essential amino acids. Great for adding to a smoothie.

Beans and Rice

Beans and rice, what more is there to say. Tasty, and staples of a good healthy diet. You can work these into your diet easily and they are probably already in there anyway. So good job!

Protein Powder

Most plant based protein powders are made up of a combination of rice, pea, and soy protein. Soy Protein Concentrate is most important here, containing eight of the nine essential amino acids, being just one short of being a complete protein on its own. Once combined with the other two its ticks that box however.

Nuts and Seeds

Plant foods don’t come much more natural than nuts or seeds. Sunflower seeds, pumpkin seeds, throw in a few nuts and you have all of the protein you need to be considered complete.

Protein? Completed it Mate

So there you have it, complete proteins. They contain all nine essential amino acids and should be a part of a healthy balanced diet to ensure you are getting all of the vitamins and minerals you need.