Why Complete Protein Matters


Why (In)complete Protein Sources Matter

Video taken from the channel: 10 Litres Fitness


Complete Protein Facts & Myths (700 Calorie Meals) DiTuro Productions

Video taken from the channel: DiTuroProductions


What is a complete protein?

Video taken from the channel: Living Better


The Protein Combining Myth

Video taken from the channel: NutritionFacts.org


6 complete protein sources for vegans

Video taken from the channel: Healthfitopedia


Complete protein-What is it and where do I get it? (Ultimate Guide to Protein Part II)

Video taken from the channel: Nutrition Made Simple!


Can Vegans Get Enough Protein? | The Exam Room Podcast

Video taken from the channel: Physicians Committee

A complete protein is a food that contains all nine of the essential amino acids in high enough amounts for our bodily functions. Typically, complete proteins are animal-based foods, such as meats, poultry, fish, milk, eggs and cheese. The only plant-based source of complete protein is soybeans. Complete protein sources contain all nine essential amino acids; these amino acids are considered essential because our bodies need them to function optimally and cannot produce them on their own. Complete proteins are most often found in animal-based foods (meats and dairy), as well as in some plant-based sources like quinoa and soy.

It’s the total amount of protein you eat over a day, not the specific type of protein you eat, that matters. Research has repeatedly shown that consuming about 30 grams of protein at mealtime. What matters is the quality of the protein, and how much of it is complete. Only complete proteins are used to rebuild your muscles. Another reason to care about the completeness of protein in your sports drink is that the nitrogen fraction of any incomplete protein must be.

Your muscles are made of protein. For your muscles to grow stronger, they need protein. If you are causing micro-injuries to your muscles by working out, protein is necessary to heal them.

Whether you have an intense workout plan or an active lifestyle, protein equips your body with what it needs to build the muscles to do what you want to do. Protein exists throughout the human body and is found in muscles, bones, skin, hair, organs, and tissues. It makes up the building blocks of enzymes, which are necessary for distributing oxygen to body parts through the bloodstream. Every human. The complete protein A complete protein is a protein that contains all of the essential amino acids, in an adequate proportion.

Not all of the proteins containing all essential amino acids may be called “the complete proteins”. Correct proportion, sufficient to support the biological functions of the body, is what makes one protein complete. Some proteins, mainly from animal sources, are called complete proteins. They contain all the essential amino acids needed for the body to use.

The incomplete proteins lack all the essential amino acids, therefore, requiring additional proteins to make them complete. A food is considered a complete protein when it contains the nine essential amino acids that our body cannot produce on its own. Let’s back up for a second and talk about amino acids. They’re organic compounds that are considered to be the “building blocks” of protein. A quick refresher from science class: Protein is comprised of 20 amino acids; 11 of these amino acids are produced by the human body.

For good health, we must get the other nine amino acids (called “essential amino acids”) from the foods we eat. When a food contains all nine of these amino acids, it is called a “complete protein.”.

List of related literature:

Complete proteins are those that contain all the essential amino acids in the quantity and proportions necessary to maintain healthy tissue repair and growth; incomplete proteins, on the other hand, lack one or more essential amino acid.

“Human Biology: An Evolutionary and Biocultural Perspective” by Sara Stinson, Barry Bogin, Dennis H. O'Rourke
from Human Biology: An Evolutionary and Biocultural Perspective
by Sara Stinson, Barry Bogin, Dennis H. O’Rourke
Wiley, 2012

Complete proteins contain all the amino acids necessary for good health, whereas incomplete proteins lack certain amino acids that the body must have to function efficiently.

“Concepts in Biology' 2007 Ed.2007 Edition” by Enger, Eldon Et Al
from Concepts in Biology’ 2007 Ed.2007 Edition
by Enger, Eldon Et Al
Rex Bookstore, Inc.,

The composition and amount of amino acids is important because an excess intake of protein results in the overload of urea-related metabolic waste in the liver and kidneys.

“The International Handbook of Space Technology” by Malcolm Macdonald, Viorel Badescu
from The International Handbook of Space Technology
by Malcolm Macdonald, Viorel Badescu
Springer Berlin Heidelberg, 2014

Proteins are essential in the body not only as structural components but also because all enzymes are proteins; many of the hormones that integrate metabolism are proteins, and so are large macromolecules such as haemoglobin.

“Science and Soccer” by Thomas Reilly, A. Mark Williams
from Science and Soccer
by Thomas Reilly, A. Mark Williams
Routledge, 2003

This was because their previous energy intake was inadequate; increasing their energy intake both spared dietary protein for the synthesis of tissue proteins and provided an adequate energy source to meet the high energy cost of protein synthesis (Section

“Introduction to Nutrition and Metabolism, Fourth Edition” by David A. Bender
from Introduction to Nutrition and Metabolism, Fourth Edition
by David A. Bender
CRC Press, 2007

Animal proteins are considered complete proteins because they contain all the indispensable amino acids in the amounts and ratios needed for protein synthesis.

“Williams' Essentials of Nutrition and Diet Therapy E-Book” by Eleanor Schlenker, Joyce Ann Gilbert
from Williams’ Essentials of Nutrition and Diet Therapy E-Book
by Eleanor Schlenker, Joyce Ann Gilbert
Elsevier Health Sciences, 2018

This is because three-dimensional protein structures are much more strongly conserved in evolutionary terms than primary amino acid sequences, and it is the threedimensional protein structure (rather than the primary sequence) which actually carries out the biochemical function of the molecule.

“Principles of Gene Manipulation and Genomics” by Sandy B. Primrose, Richard Twyman
from Principles of Gene Manipulation and Genomics
by Sandy B. Primrose, Richard Twyman
Wiley, 2013

Because the body breaks proteins down into amino acids and redistributes them, food combinations with incomplete proteins have the same effect as a complete protein.

“Linda Page's Healthy Healing: A Guide To Self-Healing For Everyone” by Linda Page
from Linda Page’s Healthy Healing: A Guide To Self-Healing For Everyone
by Linda Page
Healthy Healing Publications, 2004

Because proteins area main component of most cell structures, adequate dietary protein is especially essential during the growth years, during pregnancy, and when tissue has been damaged by disease or injury.

“Principles of Anatomy and Physiology” by Gerard J. Tortora, Bryan H. Derrickson
from Principles of Anatomy and Physiology
by Gerard J. Tortora, Bryan H. Derrickson
Wiley, 2018

After the limiting amino acid is used up, the body uses the remaining amino acids to produce energy instead of making proteins, because dietary protein cannot be stored for later use in the way that carbohydrates and lipids can.

“Biology Today: An Issues Approach” by Eli Minkoff, Pamela Baker
from Biology Today: An Issues Approach
by Eli Minkoff, Pamela Baker
CRC Press, 2003

Alexia Lewis RD

Registered Dietitian Nutritionist and Certified Heath Coach who believes life is better with science, humor, and beautiful, delicious, healthy food.

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  • Actually except for processed food, all vegetables have complete proteins. Would be weird for anything living not to contain them all if you think about it.
    Composition is another thing though

  • I don’t know if it was answered but you cannot consume 2000kal of veggies mentioned per day, lettuce for example. You body can’t digest that amount in 24h. 2000kal of lettuce is 13.3kg. It’s about cubic meter of lettuce. That why animal do eat grass most of the day. Coz it’s not very calories efficient

  • I am 73 and have not used supplements.
    Been on plant based diet for 41.
    Don’t eat meat at home and no dairy.
    I never heard of B12 untill resent years.
    I have been very healthy without B12 for 41 years!

  • OK, Very informative video with lots of good info in short time-frame nice, howeverwhat about Dr Gundry with vids currently showing interviews with him on you tube channels saying we need to cut out Lectins [ whatever they are although I’m still not clear on exactly what they are apparently harmful to our gut health ] out of our diets and beans [apparently all types] was one of those he referred to.

  • Problem is eating too many plant products you could reach a limit due to anti-nutrients which you can only process so many of. We only make so much phytase, etc.

  • Alright, look at this out of interest:
    Gorillas are primarily PLANT eaters. They weigh on average 400 pounds (180Kg). They eat on average 20Kg of plant foods per day. That means they eat on average about 100g food per/Kilogram Body Weight.
    Now If I was to eat a Gorilla diet according to my Body mass which is 64KG, I’d have to eat about 6.4 Kg of RAW plant foods per day.
    This means, 6Kg of a ‘Green apple diet’ would give me: (Low Fat, Low protein)
    % Daily Value *
    Total Fat 10g 13 %
    Saturated Fat 1.7g 8 %
    Sodium 60mg 3 %
    Total Carbohydrate 829g 301 %
    Dietary Fiber 144g 514 %
    Sugar 623g
    Protein 16g 32 %
    Vitamin D 0.00mcg 0 %
    Calcium 360.00mg 28 %
    Iron 7.20mg 40 %
    Potassium 6420mg 137 %
    However, if it was let’s say a ‘Mustard Greens diet’, it would give me a shocking Surprise! See below…
    % Daily Value *
    Total Fat 25g 32 %
    Saturated Fat 0.6g 3 %
    Sodium 1200mg 52 %
    Total Carbohydrate 280g 102 %
    Dietary Fiber 192g 686 %
    Sugar 79g
    Protein 172g 344 %
    Vitamin D 0.00mcg 0 %
    Calcium 6900.00mg 531 %
    Iron 98.40mg 547 %
    Potassium 23040mg 490 % (Again we see a low fat fat diet, but with plenty of Proteins, And sufficient Carbohydrates)
    But humans arn’t Gorillas, and there’s no way that I can eat 6Kg of Raw greens. However, an Adult Male Gorilla DNA allows him to grow to 180kg. The human DNA allows him to grow to about Half of that, i.e. 90kg. So, If I’m Following a Strictly Gorilla Diet, according to my HUMAN DNA, Id have to eat about 3kg of greens per day. This would STILL give me All the Calcium, Magnesium, Iron that’s reccommended.

    My hypothesis is that if vegans dont get enough proteins from their diet, it’s because they Dont Eat ENOUGH. And also because they dont eat ORGANIC. Inorganic plant foods are literally on par with Junk foods void of minerals and vitamins. Studies show nutritional differences of 3-20 times.

  • You forgot to mention bio availability of plant proteins. DIAAS is a measure of the bio availability of various protein sources. Most meat and dairy products have 100% bio availability. Chickpeas have 72% bioavailability, black beans 65% tofu(non gmo without roundup pesticide residues) 54%, pea isolate 82% etc.

  • You can get all the B12 you need from nutritional yeast and yeast extracts like Marmite and Vegemite tiny amounts is all you need!

  • He didn’t talk about seafood. I’m a vegan who eats small types of seafood because it’s a great source of protein. I eat it once a week. Seafood really shouldn’t be grouped with other animal products because it’s very different.

  • Oh wow. I have been vegan for a year and I didn’t know up until now that the protein combining was a myth. So many misinformed vegan advocates out there that don’t even give the right advice. Thank you dr Greger!!!!!

  • I have a family member who really wants to build muscle and follows body builders, and tries to eat like them. I’m vegan and trying to show them that they really don’t need animal protein. These body builders talk about how animal protein is more easily absorbed into the body than plant protein. I’m trying to find some evidence of this. Does anyone know if this is true or have any resources on this in particular?

  • Alhamdulillah someone finally being non-biased or triggered whilst talking about plant based vs omnivore proteins. So sick of all the arguing man. Stop stressing about pushing opinions on people because at the end of the day it’s that stress that’s going to kill you quicker than either of these dietary regimes.

  • Always highlight non vegans have high numbers of B12 deficiency. Everyone should supplement. It’s not about meat it’s about sanitation. Also let’s be clear about vitamins and minerals. Standard American diet is inherently deficient.

  • If you want to prove your point, help a vegan cyclist race at the Tour de France. Then we can discuss whether complete protein is a myth.

  • So could i be healthy on a variety of fruits and vegetables without eating grains and legumes or seeds? Just strictly vegetables and fruits??

  • Great information. Dr Barnard is very knowledgeable. Gorillas and horses are jacked but so are lions and Tigers. It would be great to hear a respectful debate between Dr Barnard and Dr Paul Saladino. Thanks for the interview.

  • Wait…he said the body strips and recycles protein from itself. Isn’t it bad when the body strips off protein? When it does this with calcium with pregnant mothers it causes bone loss and bad teeth, How is the protein thing different?

  • It’s unbelievable how much influence industry has on people. They basically lied to public with their sh***y ads and “studies”. Thanks for doing this!

  • love this video except that you said that meat is the only source of complete protein, but this is not true, because soy and quinoa.

  • No, disgraceful misinformation about children. Children should not be vegan during the most important developmental stage of their life. Stop deleting comments.

  • It’s strange but there is only 2 g of protein in 100 g of brocoli…I don’t know about you but I am not able to eat more than 2 kg of brocoli per day…. ��

  • Hi, I’m trying to construct/understand, fully, the argument to refute/debunk the food combining myth. Directly and with scientific sources. However, many materials, even the video above, use slightly roundabout ways to present the case, and oftern do not directly address it. I have a friend who recently did a training where they were specifically taught this theory and her being straight out of training, my unresearched arguments are weaker. “This is not true” is not an argument, that is a claim. An argument would contain proof and sources. The video above, which I found whilst searching for material, both scientific and popular, does not present the full argument. The articles flashed on the screen look scientific but the titles do not direclty address the quesion (I will nevertheless try and look them up, to see, if their bodies do). It can be seen as using roundabout pointers. In myth debunking this leaves too much room for potential other fallacies. So can someone help me with either constructing the argument or at least point out scientific evidence to counter the claims of food combining? I’m confortable with dwelling into scientific papers, but one needs to dive in from the right end of the pool, with right keywords to avoid wasting time. And by looking at both sides, independently of what one believes or wants to believe. I might end up with the construction of convincing opposite arguments as well. Whatever the data.

  • So lets be realistic here shall we. 50 grams of protien a day.
    To get 20g of protein, you need to eat a whopping 500g of steamed broccoli. Thats over 8 serves of broccoli!! Definitely one way to hit your 5 a day or 7 a day, but that’s a heck of a lot of broccoli to eat for one meal. Alternatively you can get 20g of protein from just 70g of grilled steak.
    I live an active life surfing, motoXcycle riding, skate boarding, mountain bike riding and many more individual sports and I am in my late 50’s. What a load of BS have a cow man.

  • Is Michael Greger s resaerch valid?
    Like there are some paid studdys, some studys that support a movement like the vegan 1.
    I mean thear is also the lchf experts and nutritionist an people claiming that they are healthyer and more energetic on it have way better blood work and stuff like that.
    I want some proff that he has valid information.

  • Methionine is found in sufficient levels in rice alone.

    Same with legumes and lysine.

    Anyone consuming, say, ONLY white rice plus a vitamin c, a, and b12 supplement would not become deficient in any amino acid (or anyhing else so long as rhey got sunlight) no matter how long they ate like that.

    Same with legumes.

  • The vegan diet is only half true. Yes the biggest animals are “vegan”, but they always leave out the fact they are RAW vegans. Those animals don’t eat cooked protein. That’s why they are so big. They literally graze all day and have the stomach acids to do it. We would have to juice that amount of greens. We need to get our protein that is already bioavailable, but cooking destroys the protein. Our bodies want amino acids, NOT protein. So, for TRUE protein, juice your greens and soak raw nuts and seeds. Done

  • He answers the same questions all the time with fake ADA data. If you are taking a supplement it’s because your diet lacks it. You eat a high oxolate diet over time you will get Primary Hypooxaluria. Vegans Drs know any diet needs 3 generations for an effect to be present. He’s a quack.

  • I’m not a vegan nor do I promote any specific diet. I believe a vegan diet can be healthy as long as vegans get all their nutrients as naturally as possible.

    Here is one nutrient that vegans must be aware of and make sure they are getting in their diet:

    Vitamin A. Naturally through foods only. The conversion rate from beta-carotene to retinal is only 20-1. And half of the population has a genetic mutation that would make the conversion rate even worse, somewhere around 40-1. The conversion rate from animal based retinol to retinal is about 1-1. Retinal finally gets converted to retinoic acid, which is also extremely vital to our bodies needs, such as the function of iron.

    This is only one nutrient. I have more that I can talk about but I’m not sure if anyone will even take my first recommendation seriously. I’m not here to start any debates. I’m just trying to help.


  • It’s interesting the way he says ‘cows don’t make calcium’. Of course they don’t. It’s an element. No one can make it. But they absorb and deliver it. To use that to say that milk is useless is I think a questionable method

  • The cows get protein from grass, so just eat grass; simple. Where does the grass get the protein from? Just eat what the grass eats; water thats traveling through dirt. Drink dirt water, its simple.

  • The sad thing is that even Vegans seems to still be as obsessed with “proteins” as the average carnist.
    In reality we don’t need to be thinking about trying to get enough protein.
    You can completely throw out the beans, lentils, nuts and seeds and still be perfectly fine.
    Eating fruits and greens exclusively will give about the same amount of proteins/aminos per calorie as mothers milk.
    Plenty enough to build strength and perfect health.

  • Portien thoery came from USSR and Nazis. Starving Dogs, humans are dogs or fucking monkeys idiots… just like the Food Pyramid is made by Dairy Farmer Corps! America is a Corp not a nation and gives no fucks like any corp.. wake the fuck up… its almost to late for yall

  • The physiques of the elite bodybuilders are not achievable with just pure plants or pure meat alone, they require exogenous drugs. Wish you would have mentioned this.

  • Jesus, i was in nutrition class and hearing my teacher telling all the jokes i mean jocks about protein combining just made me wanna flip a table, i have many regrets

  • Can you suggest what would be the best diet for a person who wishes to build a substantial amount of muscle but also wishes to live into their 80s? It seems like the most muscle-promoting protein/amino acid profiles are also the ones associated with heart disease and cancer.

  • This is good evidence that plants can offer sufficient protein with no meat. But this is poor evidence that a single-source plant can offer sufficient protein.

    The very quote you cite says that plant proteins are sufficient “as long as sources of dietary protein are varied.” Of course meat isn’t needed. But varied plants evidently are.

    The gelatin study only looked at 15 different protein sources, it was on RATS, and it is from 1964.

    Good job herding the sheeple.

  • If ye love me, keep my commandments.
    John 14:15 KJV
    Remember the sabbath day, to keep it holy.  Six days shalt thou labour, and do all thy work:
    Exodus 20:8‭-‬9 KJV

    Saturday is the day of the Lord

    The claim that Christ by his death abolished his Father’s law, is without foundation. Had it been possible for the law to be changed or set aside, then Christ need not have died to save man from the penalty of sin. The death of Christ, so far from abolishing the law, proves that it is immutable. The Son of God came to “magnify the law, and make it honorable.” [Isaiah 42:21.] He said, “Think not that I am come to destroy the law;” “till heaven and earth pass, one jot or one tittle shall in nowise pass from the law.” [Matthew 5:17, 18.] And concerning himself he declares, “I delight to do thy will, O my God; yea, thy law is within my heart.” [Psalm 40:8.] GC88 466.3

    Ecclesiastes 12:13 KJV
    Let us hear the conclusion of the whole matter: Fear God, and keep his commandments: for this is the whole duty of man.

  • He didn’t really talk about how much plant protein we absorb vs meat protein. He talked about calcium but not meat. I was really curious about that stats on that. I’ve heard that we have to consume much more plant protein than we think we need because the body can only absorb a small percentage. Where as a chicken breast is almost completely absorbable.

  • I would drink rat milk, who cares, its just your mind getting in the way to eat this but not that. the fact of the matter is most vegans went vegan then learned how to defend it as yhe superior way of eating, not the other way around. its all a superiority complex, they like to look down at others who arent vegan as less than and gonna die a miserable death while vegans fart rainblows and pee pure mango juice.

  • But I’m not a giraffe or a horse, I can’t be a carnivore and Except to be healthy like a Lion. Also can all the protein absorb?

  • But here is the twist, plant protein is not equal to meat protein, the meat protein has higher quality and with even greater quantities, so animal protein is better

  • Started watching your videos and subscribed to your YouTube and Twitter feeds after watching The Game Changers last night on Netflix. Have been vegetarian for the past 8 years. Have cut out dairy cheese and diary youghurts this year and aim to finally remove eggs from my preferred diet over the next 2 months too. VEGAN-in-process. LOVE your energy and information! I’m thrilled to be on this healthy journey. Thank you ♥

  • Hello!

    Thanks for all the great quality of information accross these videos. Especially proud as I’m also a Portuguese living abroad.

    I have read different opinions that the absortion of plant-based proteins is significantely lower than of animal-based.

    You mention that you will cover this on a future video, but I haven’t seen a part III. Did I miss this reference in one of your other videos?

    My curiosity comes from having had two serious tendon injuries in the past year after following a plant-based for two years now.. wonder if there is a relation given the importance for proper protein absortion in order to heal tendons after exercise.
    There was no obvious movement that led to the injuries, just came up slowly (medial epicondylitis and supraspinatus). These are normal injuries in climbers, but I have climbed for 10 years and have never had a non-trauma related injury before.

    Thank you in advance


  • Key concept is “typical american diet”. Which produces an overweight to obese population. But why? A look at the “requirement index” shows that milk and eggs are both in the high 90 % range and are called complete foods because of this. Whole grains are in the 76 to 82% range and peanuts are 67%. Meats, not listed, are higher than grains but lower then say, eggs. Now what does this mean? To me, if you only eat uncombined foods, you need 50% more peanuts(67% plus 50 % of 67%, or 33% equal 100%, no?) to get enough essential amino acids to supply enough for the body to have the the100% complete protein needed to live. Where does the remainder protein go? Some can be used by the body as energy, but some is also stored until the body gets the missing amino acids needed to make it useful for the body. This is called by normal language, fat. That is one reason why the “typical american diet” is so high in calories. Look at nations where excessive calories in the diet are either not available or too expensive and see what they eat. Cuba for example. There is a Cuban joke the goes:In Cuba we eat beans and rice for breakfast, rice and beans for lunch and Moros and Chritianos for dinner (read:beans and rice). There are not many fat Cubans but there are many healthy ones! India and African, same thing. No, you do not have to combein foods to get a better protein complex, unless you do not want the typical american diet.

  • In terms of protein, animal products (egg whites, chicken breast) have higher bioavailability compared to plant products. Does this matter?

  • Those animals he mentioned either have a rumen or a caecum with the correct bacteria that produce the amino acids, My caecum is called an appendix. Another interesting note is that those plant eating animals end up with 70+% of the plant material converted into short chain fatty acids-there are eating a HIGH FAT diet

  • Hello, I like the way you explain all these here. Thank you. I wanted to say that eating animal products may be a choice for the person that purchase them, but it is actually not a choice for the killed or exploided animal.

  • My RD from KP told me “you cannot eat only plant protein” you must eat animals to get all your nutrition….she sat there with all her fake meat for display>barf and I had to pay 20.00 for that consult. Ohhh and only 2 fruits a day because it has carbs and natural sugar.

  • Hi! How about methionine and cysteine, the two sulfur-containing aminoacids? Vegetable proteins have lower levels of these two, if compared to animal proteins. Isn’t that a problem when talking about protein quality and digestibility?