How much protein do you actually need per day?

What is protein?

There are three nutrients that we need in large amounts – proteins, carbohydrates and fats. 

Proteins are large molecules composed of one or more chains of amino acids in a specific order, and several of these amino acids can only be obtained through food, and therefore they are called essential amino acids. The human organism is unable to synthesise about half of the twenty common amino acids. You have to obtain them through your diet, by eating foods high in protein. Animal protein sources such as meat, fish, eggs and milk provide all the essential amino acids. Vegetables such as beans, chickpeas, peas or lentils also contain appreciable amounts of protein. However, in the case of plants, the essential amino acids are not all present; there are some that are not present at all or just in small quantities.

Why do we need it/ what is the function of proteins?

Proteins are essential for the structure, function and regulation of cells, tissues and organs of the body. Each protein has unique functions. Proteins are essential components of muscles, skin, bones and the body as a whole. Proteins are essential for the formation of enzymes, hormones and antibodies and are decisive for the maintenance of human health.

Proteins are still one of the three nutrient types used as sources of energy by the body (except for alcohol), the other two being carbohydrates and fats. Proteins and carbohydrates each provide 4 calories of energy per gram, while fats calories per gram.

According to the European Food Safety Agency, the population reference intake for adults of all ages was estimated to be 0.8 g protein/kg body weight per day.[i]

The World Health Organization (WHO) also recommends that adult women consume about 48g of protein a day, and adult men about 56g.[ii] 

In Europe, average protein consumption ranges from about 99 to 115g a day,[iii] and the WHO claims that protein deficiency was eliminated from the European Union after the Second World War. So, very few Europeans are nowadays suffering from protein deficiency. 

The question is if there is a benefit of consuming more protein even in the absence of protein deficiency. 

Unless you are elderly and have muscle wastage (sarcopenia) or you are recovering from illness, there are no benefits to eating high amounts of protein. A regular equilibrated diet provides more than the recommended amount of protein for maintaining health. People who take part in moderate exercise every couple of days do not need any additional protein. 

However, those taking daily high-intensity exercise could benefit from additional protein from food or others sources.

Protein for Athletes 

The American College of Sports Medicine in conjunction with the American Dietetic Association and Dietitians of Canada recommend daily intake of 1.2 to 2.0g protein / kg body weight [iv]. These specific recommendations for athletes are superior to those for the general population (0.8g / kg / day). This difference concerns the need for protein for certain functions, namely[v] :

1. Repair and replace damaged proteins by physical exercise at musculoskeletal, bone, tendon and ligament level;

2. Maintain an optimal function of all metabolic pathways that use amino acids;

3. Enable increased muscle mass;

4. Allow an optimal function of the immune system;

5. Allow an optimal production rate of plasma proteins

Conclusion

In summary, if you’re engaged in moderate exercise, your normal diet perfectly covers your protein needs. Only if you are usually involved in an intense training program, aiming for 1.2 to 2 grams of protein per kilogram of body weight may help you achieve your goals regarding muscle growth and strength.

·     If you practice endurance exercise, you should ingest levels at the lower end of this range.

·     If you alternate between endurance and strength training, you should go for an intermediate value, and, finally,

·     if you perform strength/power exercise, you should ingest levels at the upper end of this range.

[i] https://www.efsa.europa.eu/en/efsajournal/pub/2557

[ii] http://www.who.int/nutrition/publications/nutrientrequirements/WHO_TRS_935/en/

[iii] FAO Statistics Division 2010, Food Balance Sheets, Food and Agriculture Organization of the United Nations

[iv] Thomas, DT et al. , Nutrition and Athletic Performance. Medicine and Science in Sports and Exercise, 2016. 48(3): p. 543-568.

[v]Phillips, S.M., D.R. Moore, and J.E. Tang, A critical examination of dietary protein requirements, benefits, and excesses in athletes. International journal of sport nutrition and exercise metabolism, 2007. 17 Suppl: p. S58-76.