Protein is found in meat and dairy products, but the requirement can also be met with plant-based foods. Athletes like to use additional protein powders and protein shakes – but is that really necessary? How much protein does the body need and what are its functions?
Egg whites are proteins
It is not always clear to everyone that the two terms refer to one and the same substance: “White” is the colloquial term for protein. Along with fats and carbohydrates, proteins are among the energy-supplying macronutrients. From a chemical point of view, they consist of amino acids, of which our body needs 20 pieces to maintain its bodily functions, eight of which are essential and must be ingested with food. So we have to consume protein, which is broken down into amino acids during digestion and thus ensures the development and maintenance of muscles, organs, cartilage, bones, skin, hair and nails.
Proteins can be found in each of our cells – the different proteins fulfill different tasks: Structural proteins ensure the stability of organs and tissues, others ensure the transport of substances in the blood and in the cell, and other proteins again fulfill functions in the immune and defense system of the body, influence chemical reactions in the cells or regulate the metabolism.
protein for the muscles
Everyone now knows that the main component of our muscles is endogenous protein. This is where the belief comes from that the more protein you eat, the more muscles you can build. Therefore, especially in fitness studios, “training-optimizing” powders are often offered in order to maximize the desired muscle build-up.
What is always forgotten: The most important source of energy for our muscle motor are carbohydrates. And: Protein alone does not make muscles – only regular and effective training builds it up. Protein alone is not enough to maintain or build muscle mass.
On the contrary: Excessive protein intake can damage the kidneys burden, since superfluous protein is converted into urea and has to be carried away via the kidneys with the urine. If the kidney function is already impaired, the kidney function may deteriorate further. In healthy people, there is not (yet) enough scientific knowledge to conclusively assess the connection between protein intake and kidney function. Nevertheless, the motto “a lot helps a lot” does not necessarily apply to protein.
The high-dose intake of individual amino acids in the form of protein preparations can also lead to an imbalance in the amino acid metabolism: in animal models, this led to undersupply of other amino acids or to neurological disorders. Anyone who takes protein powder should therefore have their kidney function checked by a doctor to be on the safe side and also pay attention to the ingredients of the preparations: As the Bremen consumer center found out in 2020, many preparations contain additives, artificial sweeteners and flavors.
Protein requirements for adults
According to the German Society for Nutrition (DGE), with normal physical activity, the body (of normal weight) needs about 0.8g of protein per pound of body weight be supplied. The actual protein intake in Germany exceeds this recommendation and is around 1.2 g per kilo of body weight per day. This value corresponds exactly to what the body should be fed to build muscle during training phases.
Therefore, an additional protein intake through special protein preparations is usually not necessary. Under the most extreme training conditions, a maximum protein intake of up to two grams per kilogram of body weight is tolerable – but honestly, which one of you really trains as hard every day as an extreme athlete? And these two grams could also be achieved through normal food without special protein supplements.
How much is two grams of protein? If you are of normal weight, you can easily calculate your needs: a person weighing 70 kilos needs 56 g (70 x 0.8 g) of protein per day. With three meals a day, this corresponds to around 18 g per meal. And that in turn corresponds to 50 g of cooked tofu and 100 g of cooked mushrooms. If you are overweight, you should rather refer to the rule of thumb, according to which protein should only make up ten to 15 percent of the meal: Specifically, this is up to 20 g per meal for women and up to 25 g for men.
Incidentally, pregnant and breastfeeding women and adults over the age of 65 have a slightly higher protein requirement, but this is also on average 58 or 63 g per day.
What foods contain protein?
The “100 gram rule of thumb” is easy to remember and implement. Most protein foods contain as much protein per 100g as you need per meal: 100 g of cheese, meat, fish, nuts and legumes such as beans, peas or lentils. You can only grab it again if the water content is quite high. About 200 g of quark, yoghurt or 150 g of tofu contain 20 to 25 g of protein.
A rather unknown source of protein is also a good source of carbohydrates, namely grain. Common cereals such as wheat and oats offer an impressive 10 to 12 g of protein per 100 g. It is advisable to create a comprehensive nutritional value table and to consciously weigh the individual ingredients in order to visualize your own protein consumption. So don’t worry – you get (much) more than enough protein from a normal diet.
Biological value: is there “good” and “bad” protein?
Sure, there is a lot of protein in meat, but also in dairy products, fish and sausage. However, there are also enough plant-based foods with which it is possible to cover the daily protein consumption. If possible, the “biological value“ of the protein should be considered. She describes, how similar the ingested protein is to the body’s own protein structures and how much of it is needed to build body protein. The more the structure of the food’s amino acids resembles that of the human body, the higher the biological value.
Now it gets complicated: The Reference value for the biological value is an egg that has a value of 100. The lower this value, the more you have to absorb from this protein source in order to cover your protein requirements. Since every protein-rich food has a different amino acid composition, a combination of different protein sources can increase the biological value.
So if you serve potatoes with your fried egg, you will achieve a value of 137 and thus a much higher biological value than if you only eat the egg. Beans and corn together have a value of 101 – so it is also possible for vegans to consume protein with a high biological value. In any case, the following applies: the mixture makes the difference – the more diverse and colorful your diet, the better!
What Utopia recommends
Stay away from protein powders, protein shakes, protein bars and other products that artificially increase your daily protein intake. It’s better to control your eating habits – you’re probably already consuming (too) much protein. The more colorful and diverse your diet, the greater the chance of increasing the biological value of your protein intake. So make sure you have variety in your diet, which can also be purely plant-based.
by the way: Utopia has not only looked at protein, but also at the other two macronutrients for you. Here you read more:
- Everything you should know about cooking oils and fats
- Good carbohydrates – and which ones you should avoid: an overview
Read more on utopia.de:
- Plant-based protein: These foods are high in protein
- Protein cake without protein powder: recipe with 4 protein sources
- Vegan protein powder: 3 providers in comparison