There are thousands of different proteins. Wheat gluten, maize gluten, zein, and albumin are some examples. Any food or living organism will contain at least one protein. Eggs and seeds can have one to a few, and more complex structures like humans contain way more proteins.
This post is part of a series covering the main nutrients in our food. We’re going to have a look at what carbs, proteins, fats, fibre, minerals and vitamins do in our bodies and thus get to know why we need them. This post is dedicated to proteins.
22 proteins are important for humans
Proteins are made of mainly carbon, hydrogen, oxygen, and nitrogen. Many contain sulphur, and some contain phosphorus as well.
Like carbs, they are made up of smaller compounds called amino acids. There are about 500 amino acids known to us, but our body uses 22: Alanine, Arginine, Asparagine, Aspartic Acid, Cysteine, Cystine, Glutamic Acid, Glutamine, Glycine, Histidine, Hydroxyproline, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Proline, Serine, Threonine, Tyrosine, Tryptophane, and Valine.
Essential amino acids
Some of the 22 amino acids that our bodies use and need cannot be produced by the body itself. So we need to get them through our diet. These are: Lysine, Leucine, Isoleucine, Phenylalanine, Methionine, Valine, Threonine, Tryptophane and Histidine.
Many foods, especially those of animal origin, will contain all of these essentials, or even all of the 22 amino acids our body uses. But not all plant-based foods contain all nine essential ones. And this is where the exaggerated vegan protein panic comes from. When one eats a completely plant-based diet, it is important to eat a great variety of fresh veggies, fruits, pulses, and grains. When you do that, you ensure that you get all the amino acids and other nutrients that you need as well. Actually, this doesn’t only count for vegans and vegetarians; everyone benefits from a diverse diet.
Quinoa, soy, chia seeds, and animal-based foods are what we call complete proteins; they contain all 9 essential amino acids.
Proteins are building blocks
The body uses amino acids to build our own human proteins, which are the building blocks of our tissue. We thus need proteins for the growth and repair of our body’s cells and tissues.
They are also needed to synthesise enzymes, plasma proteins, certain hormones, and neurotransmitters. Tyrosine, for example, is needed to create dopamine, our motivational neurotransmitter. Insulin, which manages your blood sugar levels, is also made of protein.
Immune system support
Proteins also form antibodies. These are important workers of the immune system. They identify foreign things in our bodies, like pathogens, and mark them so that other employees of the immune system can easily find them and kill them.
Transport and storage proteins
We have a bunch of proteins in our bodies that transport stuff. An example is hemoglobin. This is a protein found in red blood cells, and it transports oxygen from the lungs to the rest of the body. Storage proteins bind with another substance and then store it. Ferritin is a protein that stores iron in the liver.
Energy production
Protein can also be converted into energy when it is needed, when there is not enough glucose from carbohydrates.
Enzymes (which are proteins) convert the protein into glucose, and then it can be used to generate ATP, our energy molecule. You can read more about ATP in this post.
What’s the best protein?
For our body, it is quite efficient to receive proteins that contain those essential amino acids in the ratios that our human body needs them. Then it doesn’t need to spend much energy processing, converting, and rearranging amino acids to create its human proteins. We call this the biological value of protein; the higher it is, the ‘better’ the protein is.
For us humans, egg protein has a very high biological value. However, don’t go nuts on eggs now, because they are also quite high in cholesterol and overall not the most healthy food in the world. It is more balanced to get your protein from different sources, like a variety of pulses and veggies, and to not eat a lot of protein.
Why shouldn’t we eat a lot of protein?
We definitely need protein; however, the body has no use for excess protein. It does not store protein, or amino acids, for later use like it does with the glucose from carbohydrates.
Excess proteins need to be stripped of their nitrogen parts, and the liver turns this into urea. Urea is then excreted by the kidneys in your pee. This process takes up quite some energy, that we could spend elsewhere if we wouldn’t eat so much protein.
After nitorgen is removed, the leftover part of the protein can be used to generate energy. If energy is not needed, it gets converted to glycogen or stored as fat.
If excess protein isn’t useful for the body, it might make you wonder: why do athletes eat so much protein? The answer lies in protein’s role in muscle repair. When we engage in strenuous activities like resistance training or intense cardio, our muscles experience tiny tears. This is part of the natural process of building strength, but effective recovery requires protein. Consuming adequate protein after workouts can significantly enhance muscle protein synthesis, promoting recovery and growth.
Difficult to digest
Some proteins, like wheat gluten, can be quite difficult for the body to digest. If your digestion system is not functioning optimally, then it is likely that the wheat protein that you eat will not be properly digested. Improperly digested particles will pass from the small into the large intestine, where they can stick to the intestine’s wall and bacteria can start to feast on them. This is not a nice party! Putrefactive processes will start that generate foul or even toxic substances. These can pass from your large intestine into the bloodstream and overwhelm the liver.
Proteins, in short
Proteins are essential, as they are the building blocks of tissues, hormones, neurotransmitters, enzymes, and antibodies. They also transport and store certain substances that our body needs. I advise you to get your proteins from a diversity of foods and to go easy on animal protein, wheat, and rye. Big quantities of these foods do not support our health as well as the proteins of pulses and fresh veggies do.
Cover picture
Yup, that’s me! Before I moved to the jungle, I greatly enjoyed my weekly pole dance classes at Deep Dance Pole Dance Studio. It’s a beautiful sport that helps you develop not only confidence but also balance, flexibility, and an incredible amount of mental and physical strength! Despite our need to build muscle, we weren’t really into protein shakes, though I know some of them are very good in coffee……enjoyed in moderation… 😉
Sources:
https://www.mdpi.com/2304-8158/13/11/1771
https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.665968/full
https://www.ncbi.nlm.nih.gov/books/NBK234922
Ross and Wilson, Anatomy and Physiology in Health and Illness
On average, 100 grams of cooked Paiche provides approximately 20–25 grams of protein, making it a high-protein food. You can buy it at many markets, dried and salted, like you can see in the picture of Dirk Meyer (WikiCommons).