Protein is "THE" building block in the body. It consists of up to 50,000 protein compounds with vital functions. From muscles, skin, connective tissue, blood vessels, internal organs to hormones and enzymes – proteins are needed everywhere. Vital protein compounds are also needed for many biologically active substances, which provide, e.g., for the transport of iron or oxygen in the blood, for the immune system or bone metabolism. Protein makes up the largest proportion of human body mass in adults, at about 10 kg (about 22 lbs). The dry weight of many body cells consists of more than 50% protein.
Although protein is one of the energy-providing macronutrients along with fats and carbohydrates, it occupies a special position because it is never primarily stored in the body as energy. Unlike fats, which are stored in adipose tissue, and carbohydrates, which are stored as glycogen in the liver and muscle, proteins always have a specific function.
That is why protein is also an indispensable part of our nutrition. Whether vegetable or animal protein - in the stomach and intestines, the digestive juices break down the food protein into its smallest components, the amino acids.
To keep all vital processes running, amino acids must be available in sufficient quantities at all times. This is because thousands of repair processes take place in every cell every day, during which complex proteins are broken down into their individual components and are renewed.
Recommended daily protein requirement
If protein is lacking, it quickly becomes noticeable. Nails, hair and skin suffer, they become brittle, dull and wrinkled. Physical strength is also diminishing. We get tired quickly and are often exhausted for no reason.
How much protein is healthy for the individual cannot be answered in general terms. The German Nutrition Society (DGE) as well as the WHO recommend eating at least 0.8 g of protein per kg of body weight daily (0.36 grams per lbs).
A "high-protein" nutrition is considered to be, when 30 percent of food energy is absorbed in the form of protein. According to scientific studies, a nutrition rich in proteins can prevent some diseases of civilization. For example, studies have concluded that high-protein food can improve the metabolic condition of type 2 diabetes mellitus, lower liver fat, reduce inflammatory processes and improve the overall lipid profile in the blood.
Although we actually consume plenty of protein-rich foods, the positive effect is lost. Scientific research brings it to light: it is primarily due to the combination of “a lot of protein paired with unhealthy nutrients.". Our nutrition usually looks like this: lots of meat and sausages with plenty of additives. We neglect vegetables and fruits and absorb too little fiber and polyunsaturated fatty acids. This increases the risk of lipometabolic disorders, diabetes or cardiovascular diseases, despite a high-protein nutrition.
Protein quality - Biological Value
In addition to the appropriate protein intake, the quality of the protein is particularly important. The quality of the protein is defined by the eight essential amino acids. The dietary proteins have a different composition and the quality of the dietary proteins is calculated on the basis of the limiting essential amino acid in each case. In this case, it is not the highest possible protein content of the food that is decisive for the quality of the protein, but how much of this protein content can be converted into the body’s own protein.
In general, plant proteins have a lower value than animal proteins, which are more similar in composition to the human amino acid profile.
Higher biological values can be achieved by clever combinations of foods. If a food contains smaller amounts of certain amino acids, it can be supplemented with another food that has an excess of these amino acids. In general, it is recommended to combine animal with plant protein sources in order to achieve a higher biological value. However, it must always be taken into account that the individual protein components must be consumed in a certain proportion in order to utilize the optimum effect. For example, 35% potatoes combined with 65% cottage cheese results in a biological value of approx. 136, or 22% potatoes and 78% beef have a biological value of 114.
A supply of dietary proteins with a high biological value also has a positive overall effect on the acid-base balance, because most of the amino acids supplied can be utilized by the body. When eating foods with a low biological value, on the other hand, an excess of amino acids accumulates that are not needed by the body in the first place and have to be buffered or neutralized and excreted accordingly, which overtaxes the body and metabolism in the long run. An accumulation of acids blocks the metabolism. This has an effect on the well-being. Fatigue and lack of concentration can be acompanying symptoms. Inflammation, muscle and joint complaints often occur, and weight loss is also delayed.
Protein powder - Sense or nonsense?
Protein powders or protein shakes are no longer only popular among bodybuilders - recreational athletes are also increasingly using the diverse range of protein powders and ready-to-drinks (RTD) to build up muscles or lose weight. Nevertheless, there are always critics who refer to these additional protein portions as superfluous or even unhealthy.
Protein powders are available in concentrates, isolates or hydrolyzates. The first two forms differ only in their protein content (concentrate 80%, isolate 90%). In the hydrolyzate, the proteins have already been broken down into smaller amino acid chains and thus enter the blood more quickly. However, this leads to the fact that the amino acid concentration in the blood increases faster, with the consequence that the amino acids are increasingly used for energy production instead of protein synthesis, which are actually important for muscle building.
Protein shakes are also often used for weight reduction. Over a short period of time, this can be a useful meal replacement, especially if the shake replaces the evening meal. This additionally boosts the metabolism and at the same time achieves a long-lasting feeling of satiety. However, when choosing protein powders, the composition should be closely scrutinized. Often, the various protein shakes contain, in addition to high-quality protein, a variety of additives and also sugar, which block the metabolism and have a negative impact on weight loss.
Metabolic Balance and the macronutrient Protein
At Metabolic Balance, the macronutrient protein is also an important component in our nutrition plans. The targeted selection of high-quality animal and plant protein-rich foods, which are combined with vegetables and fruits, creates the basis for a balanced metabolism. The body is supplied with all the valuable protein building blocks and at the same time, excess acids produced during metabolism can be neutralized more easily by the vitamins and minerals from vegetables and fruit.
For a healthy nutrition, it also makes sense to consume different protein sources (e.g. fish, meat, eggs, cheese, sprouts, legumes, mushrooms, seeds or nuts) in a certain proportion throughout the day. In addition, it has proven to be particularly advantageous that only one type of protein per meal contributes to a rapid balancing of the acid-base balance, as hyperacidity can be largely avoided and at the same time the de-acidification of the body is supported.
In addition to the quality of the protein and the frequency of its consumption, the arrangement of the meals with protein is also an important pillar for Metabolic Balance. That means if you want to gently balance your metabolism and relieve the digestive organs, you always start your meal with one or two bites of the protein component. This way, the pancreas first produces the hormone glucagon, which is necessary for protein digestion, and the production of insulin is reduced. This, in combination with complex carbohydrates (vegetables, whole grains), forms a long-lasting fullness and the absence of cravings.
Sources:
Bill Campbell, Richard B Kreider et.al: International Society of sports Nutrition position stand: protein and exercise; Journal of the International Society of Sports Nutrition (2007)
Mag.rer.nat. Eddie Semler: Eiweiß unter Verdacht; UGB-Forum 3/2003, S.122-124
Jiaqi Huang, Linda M Liao et.al.: Association Between Plant and Animal Protein Intake and Overall and Cause – Specific Mortality; JAMA Intern Med. 2020 Sep 1; 180(9) DOI: 10.1001/jamainternmed.2020.2790