Tofu, almond milk, vegan cheese and Beyond Meat - the plant-based alternatives that replace traditional animal protein sources such as meat and cheese are numerous and are becoming increasingly popular. "Eating meat is no longer in keeping with the times and is damaging the environment," is the opinion of passionate advocates of plant-based alternatives. Younger generations in particular want to eat more environmentally-consciously and are increasingly switching to vegetarian or vegan lifestyles in the hope of cushioning the mistakes of previous generations and making better decisions for our planet. However, scenes of rainforests being cut down for soy production also make us doubt this way of thinking.
What is right? And what is really behind the new nutritional trend? What motivates people to replace animal proteins with vegan alternatives, what are proteins actually and what do the studies say? We would like to clarify all of this in this article and come to a conclusion about what an environmentally conscious and sustainable diet with the best possible nutritional value should look like.
What are proteins?
Proteins are essential for us humans. There are more than 100,000 proteins in the human body. In the past, and in some cases still, proteins were also referred to as albumins. This term can be traced back historically to the first isolation of a protein from chicken egg white. However, biologists at the time were able to determine relatively quickly that proteins are not found exclusively in chicken eggs, but in almost every living cell.
Depending on their composition, proteins are involved in countless processes in the human and animal body and are therefore vital for survival. Proteins are made up of 20 amino acids, which can be broken down using a written name based on the "head-to-tail" connection. Amino acids ensure that the cells in our body can renew themselves and multiply.
An example protein is usually made up of 300 different amino acid sequences. There are countless amino acid sequences that form different structures with just as many functions. The amino acids in our body are renewed and exchanged throughout our lives - this important process is called protein biosynthesis. For this very reason, it is important that we regularly consume high-quality and different proteins or amino acids.
But how do animal proteins differ from plant proteins?
Animal proteins
Basically, proteins, whether of animal or plant origin, consist of amino acids. These proteins differ in their respective structures and amino acid profiles. A soybean therefore sometimes contains the same amino acid as chicken or cow's milk.
Animal proteins often contain more essential amino acids than plant proteins. Our body cannot produce essential amino acids on its own, but must absorb them through food. Our body can produce non-essential amino acids itself, which is why we do not need to absorb them in the same quantities as essential amino acids through food.
An important term with regard to proteins is the so-called biological value. The biological value gives us information about the quality of proteins in food.
The aim of biological value is an optimal and balanced protein metabolism. It is therefore important to know how much of the dietary protein we consume can be converted into our body's own protein. Animal proteins, such as chicken eggs, chicken, beef and salmon, have a very high biological value.
But what about plant proteins?
Plant proteins
Plant foods such as quinoa, oatmeal and peas can also be high-quality sources of protein.
Many plant proteins often contain all 20 amino acids, but some of them only in limited quantities. This limited number of amino acids is known as the “limiting amino acids” in plant proteins. They are the reason why a diet based exclusively on plant proteins can lead to a deficiency of certain essential amino acids in humans.
Digestibility and bioavailability also distinguish plant proteins from animal proteins.
The so-called DIAAS, the index for digestible, essential amino acids, determines the digestibility of dietary proteins and is expressed in values below or above 100.
A DIAAS value above 100 means that a protein has a very high digestibility and is therefore of high quality for human protein metabolism. DIAAS values below 50 indicate a low protein quality, as these proteins are difficult to digest and can only be used with difficulty and to a limited extent by the human body. Animal proteins often have a higher DIAAS value than plant proteins. For example, wheat and almonds have a DIAAS value of 40, while whole milk has a value of 114 and chicken breast has a value of 108.
Reasons to replace animal proteins
Why do so many people replace animal protein sources when they often have better biological value and higher protein quality?
The main reason for this is probably animal welfare and factory farming, which have drastically worsened the quality of life of animals and also the quality of animal proteins in recent decades.
Animal Husbandry, Environment & Animal Welfare
Factory farming, poor living conditions for animals and the love of animals are some of the main reasons why many people have switched to a vegetarian or vegan lifestyle in recent years.
Many people who do not want to consume meat under inhumane conditions are rightly changing their minds.
The minority of vegetarians and vegans say that they avoid animal proteins for taste or health reasons.
However, we now know that many vegetarian or vegan protein sources, such as soybeans or almonds, lead to the extinction of animals in the rainforest, are one of the reasons for the global decline in bee populations and can have devastating consequences for the environment. Many vegetarians and so-called flexitarians say that they would rather eat animal products from sustainable and organic farming than completely avoid animal proteins.
In addition, countless doctors are increasingly pointing out that a purely vegan diet can lead to bacterial overgrowth in the intestines, which can result in chronic intestinal disorders, depression and other health problems. Vegan and vegetarian diets are therefore not suitable for everyone and are not necessarily more animal-friendly or environmentally friendly than a conscious and sustainable diet with animal protein sources.
Problems with plant-based proteins
The poor digestibility and so-called anti-nutrients in plant-based foods, such as protease inhibitors and other indigestible substances in plant-based foods, can make a purely vegetarian or vegan diet problematic. Studies have shown that the substances known as anti-nutrients in plant-based foods can have a negative impact on protein metabolism in the human body. The important, essential amino acids in foods cannot be fully absorbed by the body due to these anti-nutrients - our protein metabolism/protein biosynthesis is inhibited.
Consuming all 20 amino acids in sufficient quantities is important for our general health. Animal proteins provide a higher quality of digestibility and bioavailability of these 20 amino acids and can be ideally metabolized by the body.
For this reason, from a nutritional point of view, it is advisable to partially supplement a predominantly vegetarian/vegan diet with high-quality and digestible proteins from animal protein sources, such as salmon, dairy products and chicken.
studies on body size
A study on the correlation between height and growth in children in connection with cow's milk and plant-based "milk drinks" found that children who did not consume cow's milk had slower body growth than those children who drank cow's milk.
Since we already know that amino acids are essential for cell growth and cell renewal in our body cells, there is a scientifically based connection here that is worth considering.
Conclusion – It's all about the mix
We humans are so-called omnivores. Over the course of evolution, our bodies have adapted as best as possible to our previous diets, which is why our bodies are optimally designed and able to cope with a mixture of plant and animal proteins. Proteins from purely plant sources can not only lead to a lack of amino acids, but can also inhibit our protein metabolism through so-called anti-nutrients.
On the other hand, if we consume animal proteins in addition to plant proteins and these animal proteins come from sustainably produced production that works according to the credo of regenerative agriculture with a focus on animal welfare, we can also meet our need for a fair and animal-friendly environment without putting our health at risk. Meat consumption should always be practiced consciously and only occur with meat from organic farming, where animal welfare is not neglected.
The fact that vegan and vegetarian products such as almonds and soybeans often have a devastating impact on the environment is another argument that a vegan or vegetarian lifestyle is not necessarily more environmentally friendly. Animal and high-quality protein sources such as milk and cheese also do not always result in the death of an animal. Apart from that, animal proteins are of a higher quality if they do not come from factory farming, but from sustainable and organic farming.
We at BE THE CHANGE also speak out actively and vehemently against factory farming and for animal welfare. We source all of our ingredients and food from farms and producers who practice regenerative agriculture and focus on animal welfare. We have personally selected these farms.
A purely plant-based diet with a complete avoidance of animal proteins is not only difficult to achieve for the majority of people, but can also result in health problems or lead to a deficiency in amino acids.
For this reason, a conscious diet consisting of both plant and animal proteins is recommended.
Sources:
https://www.spektrum.de/lexikon/biologie/proteine/54137
https://www.eufic.org/de/in-unserem-essen/artikel/was-sind-proteine-und-which-funktionen-erfullen-sie-im-korper/
https://www.sciencedirect.com/science/article/pii/S1756464622000081
https://www.focus.de/gesundheit/ernaehrung/vegan_und_vegetarisch/jetzt-isst-sie-wieder-eier-und-fisch-vegane-ernaehrung-zerstoerte-darm-von-influencerin-aerzte-zogen-not Bremse_id_10485973.html
https://pubmed.ncbi.nlm.nih.gov/28592600/