Protein is an essential nutrient for the human body. Every cell in our body – muscles, tissues, organs, skin, bones, hair, nails – contains at least one of the more than 10,000 types of protein that have been identified. It is no exaggeration to say that proteins are the essential structural component of the body, for us to be able to exist, and what is more to remain healthy and functional.
Proteins help the body to:
- “repair” cells and produce new ones
- carry oxygen to the blood
- produce antibodies
- fight infections and other diseases
Precisely because protein is so valuable to our body, its lack in our diet can lead to serious health problems. On the other hand, most experts agree that consuming too much protein is not an ideal condition either.
How much protein does the human body need?
According to the Dietary Guidelines jointly compiled by the US Departments of Agriculture and Health, protein should make up 10% to 35% of a person’s daily caloric intake.
- Children under 4 years: 13 grams
- Children from 4 to 8 years: 19 grams
- Children from 9 to 13 years: 34 grams
- Women and girls over 14 years: 46 grams
- Boys from 14 to 18 years: 52 grams
- Men 19 years and older: 56 grams
Note: In nutrition science, “grams of protein” refers to the number of grams of the macronutrient protein, not the number of grams of protein-containing foods, such as meat, eggs etc.
These quantities are obviously indicative and can be personalized according to the needs of each person. Athletes, pregnant or lactating women, etc., may need to consume larger amounts. People over 40 may also need larger amounts since muscle mass loss is greater from this age.
Of course, the amount of protein we get from our diet should not be our only concern. It is important to make sure we are also getting good quality protein.
Proteins are classified into animal and vegetable, depending on their origin. They are further classified into complete and incomplete. Complete are those kinds of proteins containing all eight essential amino acids, and in this category are included all animal proteins, and some plant proteins, such as soy. Most plant proteins are incomplete.
Sources of high-quality protein include:
- Fish and seafood
- Red and white meat
- The eggs
- Cold meats
- Cheese and other dairy products