Why proteins are not only essential for athletes
Agil Nature
Proteins as a fundamental building block of the organism
Proteins are essential macronutrients that play a key role in numerous physiological processes. They are relevant not only for muscle building, but also for cell regeneration, immune defense, enzyme production, and many other biological functions. Adequate protein intake can be crucial for maintaining health , especially during periods of increased demand, such as during growth, pregnancy, aging, or certain diseases. This article highlights the diverse functions of proteins and explains why adequate protein intake is beneficial not only for athletes.
Structure and biological significance of proteins
Proteins consist of amino acids linked together by peptide bonds. A distinction is made between essential and non-essential amino acids. Essential amino acids must be obtained through food because the human body cannot synthesize them itself. Proteins are essential building blocks of muscle tissue, skin, hair, enzymes, hormones, and antibodies. They are also involved in the regulation of numerous metabolic processes. High-quality protein sources include both animal foods such as meat, fish, dairy products, and eggs, as well as plant sources such as legumes, quinoa, nuts, and seeds.
Physiological functions of proteins
Proteins perform a variety of functions in the human organism:
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Muscle protein synthesis and maintenance of muscle mass : Adequate protein intake supports muscle building, maintains existing muscle mass and prevents age-related muscle loss (sarcopenia).
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Energy metabolism and satiety regulation : Proteins contribute to increasing the basal metabolic rate through their thermogenic effect and promote a long-lasting feeling of satiety, which makes them particularly valuable for weight management.
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Immunomodulation : Immunoglobulins and other immune factors consist of proteins and are essential for infection defense and wound healing.
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Regeneration and cell growth : Proteins are essential for cell proliferation, tissue repair and wound healing.
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Enzyme and hormone production : Numerous enzymes and peptide hormones such as insulin or growth hormones consist of proteins and regulate essential metabolic processes.
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Structural functions : Collagen and elastin are essential for the stability of skin, tendons, ligaments and bones.
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Neurotransmitter formation : Certain amino acids, such as tryptophan and tyrosine, are precursors of important neurotransmitters involved in the regulation of mood and cognition.
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Blood sugar regulation : A high-protein diet can help stabilize blood sugar levels by modulating insulin secretion and reducing cravings.
Benefits and supplementary importance of protein powders
Although a varied diet is usually sufficient to meet protein needs, there are situations in which targeted supplementation may be useful:
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Optimized nutrient supply : Protein powders are a time-efficient and easily digestible source of protein.
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Muscle protein synthesis and regeneration : Especially in the post- exercise period, protein shakes can support the anabolic metabolic process and accelerate muscle regeneration.
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Increased needs in specific populations : Pregnancy, breastfeeding, advanced age and certain medical conditions often require increased protein intake.
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Vegetarian and vegan diets : Plant-based protein powders (e.g. from peas or rice) can help compensate for potential deficiencies in a purely plant-based diet.
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Practicality and flexibility : Protein powders can be easily incorporated into various dishes, such as smoothies, yogurt, soups or baked goods.
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Counteract catabolic processes : During intense exercise or long periods of fasting, targeted protein intake can prevent muscle loss.
Protein requirements: recommendations and adjustment of needs
The recommended protein intake for healthy adults is approximately 0.8 g per kg of body weight per day. However, in certain population groups, the requirement may be significantly higher:
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Athletes: Depending on the training intensity, the recommended requirement is between 1.2 and 2.0 g/kg body weight.
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Pregnant and breastfeeding women : An increased protein intake of 1.1–1.5 g/kg body weight is recommended.
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Older adults : An intake of at least 1.0–1.2 g/kg body weight may help reduce age-related muscle loss.
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People with metabolic stress (e.g. postoperatively or in cases of chronic diseases) : A protein intake of up to 2.0 g/kg body weight can promote the healing process and support the maintenance of muscle mass.
Potential risks of excessive protein intake
While a protein-rich diet is generally well tolerated by healthy individuals, it is advisable to keep a few aspects in mind when significantly increasing protein intake:
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Renal nitrogen excretion : The breakdown of excess protein leads to the formation of urea, which is excreted by the kidneys. People with known kidney problems should therefore adjust their protein intake in consultation with a healthcare professional. However, healthy individuals with normal fluid intake are generally not at risk.
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Maintaining acid-base balance : A protein-rich diet should ideally be supplemented with alkalizing foods such as vegetables, herbs, and fruit. This helps maintain a balanced acid-base balance and minimize metabolic stress.
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Keep an eye on macronutrient distribution : Increased protein intake should not come at the expense of important carbohydrate and fat sources. A balanced diet remains essential to ensure both energy availability and hormonal balance in the long term. Through targeted planning, protein-rich diets can be optimally integrated.
Influence of protein quality on bioavailability
Not all proteins are equal in terms of their biological value. Biological value describes how efficiently a protein can be converted into the body's own protein. Animal proteins generally have a higher biological value than plant proteins. However, by carefully combining plant proteins, such as rice and pea protein, an optimal amino acid composition can be achieved.
Conclusion: Proteins as an integral part of the diet
Proteins are far more than just a macronutrient for muscle building. They are essential for cell growth, immune function, metabolism, and regeneration. Adequate protein intake contributes to maintaining health and can prevent age-related muscle loss and metabolic imbalances. Choosing high-quality protein sources and consuming protein as needed are crucial to achieving long-term health benefits. While a balanced diet generally ensures adequate protein intake, protein powders can be a useful supplement in certain situations. It is crucial to individually adjust protein intake to specific needs and lifestyle circumstances to ensure optimal physiological function.
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