Proteins: what are they?
There are 3 main groups of nutrients from which the body builds, renews and extracts energy to support both basic metabolism and higher intensity efforts.
They are carbohydrates, commonly known as 'sugars', lipids or 'fats', and proteins, whose functions are essential.
Proteins are made up of chains of elements called amino acids.
There are 21 amino acids, each with a specific name, formula and function.
8 amino acids are different from the others because they cannot be synthesised by the body and must be provided by essential foods.
They appear on certain nutritional labels and it is interesting to know how to identify them:
What are proteins good for?
Proteins have two functions: structural and metabolic.
- The structural function includes everything related to the composition of tissues, muscle fibres, hair, skin, nails and organs.
- The metabolic function involves all the chemical reactions that are essential for the proper functioning of the organism and in which proteins are involved, mainly as enzymes, hormones, transporters or immunoglobulins in the case of immune defence.
They are also necessary for hormones and digestion.
Note: Proteins are not stored, so they must be consumed regularly in the diet in adequate amounts. A distinction is usually made between proteins of animal and plant origin.
Animal proteins
- Fish is easier to digest than meat.
- White meat is less acidic than red meat.
- Eggs are very digestible and can be eaten regularly, provided that the cooking process preserves the raw yolk (boiled, soft-boiled, fried).
Indicative protein content of the main categories:
- Meat: 18 to 30g of protein per 100g
- Fish: 15 to 25g of protein per 100g
- Eggs: 13g of protein per 100g
Some notes on dairy products:
- Avoid cow's milk, which is generally indigestible.
- If possible, choose dairy products made from raw, unpasteurised milk.
- Lactose-free dairy products are easier to digest: sour milk, yoghurt, cheese.
- Give preference to products made with milk from small animals (sheep, goats).
Vegetable proteins
Vegetable proteins are an excellent part of a balanced diet.
For people on a vegetarian or vegan diet, it is important to ensure a regular intake of plant proteins and to regularly check their vitamin B12 levels.
This vitamin, which is mainly found in animal products, is essential for cell renewal, red blood cells and brain function.
The protein content of the main vegetable categories:
- Cereals: 3 to 15g protein per 100g (rice, quinoa, wheat, barley, spelt, etc.)
- Legumes: 7 to 15g of protein per 100g (lentils, chick peas, etc.)
- Soya: contains all amino acids, 10 to 20g of protein per 100g
- Seaweed: contains all amino acids, 10 to 20g of protein per 100g
- Oilseeds: 10 to 20g per 100g (almonds, peanuts, cashews, walnuts)
Some indications:
- Quinoa and buckwheat contain all the essential amino acids.
- Soya should be eaten in moderation and without GMOs.
- The combination of grains + pulses (rice + lentils) is generally indigestible.
- Oilseeds are eaten after soaking in water overnight and rinsing.
- Pulses are cooked after soaking overnight.
- Chia seeds, green vegetables and mushrooms are also good sources of protein.
- To aid digestion, it is advisable to eat only one source of protein per meal.