Why protein is so important for the body
Alongside carbohydrates and fats, proteins are one of the three main nutrients in our diet. They are made up of amino acids and perform numerous functions in the body: they form muscles, enzymes, hormones and antibodies, are involved in oxygen transport and support wound healing. Without sufficient protein intake, the body cannot build tissue or maintain important metabolic processes over the long term.
Nine of the roughly twenty amino acids are essential – meaning the body cannot produce them itself and depends on dietary intake. A balanced protein-based diet ensures that these building blocks are available in sufficient quantity and quality.
Calculating protein requirements: how much is enough?
The German Nutrition Society (DGE) and the Austrian Nutrition Society (ÖGE) recommend a daily intake of around 0.8 grams of protein per kilogram of body weight for healthy adults. For older people aged 65 and over, around 1.0 g/kg is recommended, as the body uses protein less efficiently with age and preserving muscle mass becomes particularly important.
Example calculation
A person weighing 70 kg with a predominantly sedentary lifestyle needs:
- 70 kg × 0.8 g = 56 g of protein per day
Anyone wishing to calculate their protein requirement can use this simple formula as a guideline. However, the actual requirement depends on several factors:
- age and sex
- body composition (muscle vs. fat percentage)
- activity level
- state of health (e.g. after surgery, with chronic conditions)
- pregnancy and breastfeeding
Protein and sport: higher requirements for active people
People who exercise regularly generally have an increased requirement. Training causes fine micro-injuries in the muscles, which are then repaired and strengthened – and protein supplies the necessary building blocks. Studies and professional bodies such as the International Society of Sports Nutrition suggest the following guideline values for protein in sport:
- Endurance sports (moderate): approx. 1.0 – 1.2 g/kg body weight per day
- Strength training and muscle building: approx. 1.4 – 2.0 g/kg per day
- Dieting phases with muscle preservation: up to 2.0 – 2.2 g/kg per day
Important: more is not automatically better. A very high protein intake usually provides no additional benefit in healthy people and can place an unnecessary burden on metabolism. People with impaired kidney function should discuss their intake with a doctor.
Timing and distribution
Current recommendations suggest distributing protein intake evenly across three to four meals, with around 20 – 30 g of protein per meal. This stimulates muscle protein synthesis several times a day. After exercise, a protein-rich meal within about two hours can support recovery.
Suitable protein sources at a glance
The quality of a protein depends on its amino acid profile and its digestibility. A combination of animal and plant sources is usually advisable.
Animal sources
- lean meat (chicken, turkey, beef)
- fish and seafood
- eggs
- dairy products (quark, yoghurt, cottage cheese, cheese)
Plant sources
- pulses (lentils, beans, chickpeas)
- soy products (tofu, tempeh, edamame)
- nuts and seeds
- wholegrain cereals and pseudocereals (oats, quinoa, buckwheat)
Combining different plant sources – such as cereals with pulses – can significantly improve the biological value. A purely plant-based diet can also meet protein requirements, provided it is varied.
Protein powders and bars: useful or unnecessary?
Protein supplements are not strictly necessary for most people. Those who eat a balanced diet usually meet their needs easily through food. In certain situations, however, powders or bars can be practical:
- with very high requirements (e.g. intensive strength training)
- with poor appetite or in older age
- during recovery from illness
- when intake through a normal diet is limited
The quality of the product is important. It is worth checking the list of ingredients – many bars also contain larger amounts of sugar or fat.
Signs of insufficient protein intake
A mild deficiency often goes unnoticed in everyday life. Possible indications can include:
- declining muscle strength and muscle loss
- longer recovery times after exercise
- brittle nails and hair loss
- frequent infections
- increased tiredness
Older people, those with reduced appetite and people on a one-sided diet are particularly at risk of consuming too little protein.
Practical tips for everyday life
- Make breakfast protein-rich: for example quark with berries, oats with milk or an egg.
- Include a protein source in every main meal: pulses, fish, poultry, tofu or dairy products.
- Choose snacks wisely: nuts, yoghurt or cottage cheese instead of sugary alternatives.
- Combine plant-based foods: for example lentil soup with wholemeal bread or rice with beans.
- Drink enough fluids: a higher protein intake goes hand in hand with a higher fluid requirement.
Conclusion
Protein is an essential building block for health, performance and recovery. While around 0.8 g per kilogram of body weight is sufficient for most healthy adults, requirements can be significantly higher for physically active people, older adults or during particular life stages. A conscious choice of high-quality sources and even distribution throughout the day help to supply the body optimally. Anyone unsure whether their intake is appropriate can discuss their individual needs with a doctor or a qualified nutrition professional.
This article does not replace medical advice.