Protein is one of the nutrients that we talk about a lot, often in the context of sports or diets. But their role goes far beyond these areas alone: they are involved in almost all the biological functions of my body. So how much do I need per day? Where to find them? Am I consuming enough, or too much? Answers based on current scientific data.
1. What is protein used for in my body?
Proteins are macromolecules made up of chains of amino acids. They play a fundamental structural and functional role in the body. Concretely, they are involved in:
- ●The construction and renewal of muscle, bone and skin tissues
- ●The synthesis of digestive enzymes and hormones (insulin, growth hormones, etc.)
- ●The functioning of the immune system, via the production of antibodies
- ●Transport of oxygen in the blood (hemoglobin) and certain nutrients
- ●Regulation of satiety: proteins are the most satiating macronutrient, according to several studies in clinical nutrition
Of the 20 amino acids that make up proteins, 9 are called "essential": my body cannot make them itself and must obtain them through food. This is why the quality and diversity of protein sources are as important as the quantity.
| Profile | Protein requirement | Example for 70 kg |
|---|---|---|
| Healthy sedentary adult | 0.83 g / kg / day | ~58 g / day |
| Active adult (activity moderate) | 1.0 to 1.2 g / kg / day | 70 to 84 g / day |
| Athlete practicing intense activity | 1.4 to 2.0 g / kg / day | 98 to 140 g / day |
| #B2DFDB;color:#374151;vertical-align:top;background:#F4FBFA">1.0 to 1.2 g / kg / day | 70 to 84 g / day | |
| 10 to 28 g / day depending on the trimester | According to medical recommendation |
2. What are my real protein needs?According to ANSES recommendations (2021), the recommended daily protein intake varies depending on my profile:
In France, consumer studies show that the majority of adults meet their protein needs, or even slightly exceed them. The real issue is therefore not so much quantity as the quality and diversity of sources.
| Food | Proteins / 100 g | Category | |
|---|---|---|---|
| Canned tuna | ~26 g | Animal | |
| Chicken (white) | ~25 g | Animal | |
| Lean beef steak | ~22 g 13px;border:1px solid #B2DFDB;color:#374151;vertical-align:top;background:#F4FBFA">Cooked lentils | ~9 g | Plant |
| Edamame (soy) | ~11 g | Vegetable | |
| Firm Tofu | ~8 g | Plant | |
| Hemp seeds | ~32 g 13px;border:1px solid #B2DFDB;color:#374151;vertical-align:top;background:#F4FBFA">Whole egg | ~13 g | Animal |
| Quark 0% | ~8 g | Animal | |
| Cooked quinoa | ~4 g | Plant |
3. Animal vs. plant proteins: what’s the difference?
Animal proteins (meat, fish, eggs, dairy products) contain all essential amino acids in proportions adapted to human needs. They are called “complete” proteins.Plant proteins (legumes, cereals, oilseeds, tofu, tempeh, etc.) are often "incomplete" in isolation, because they lack one or more essential amino acids. However, supplementation between plant sources makes it possible to achieve a complete profile:
- ●Legumes + cereals: lentils and rice, hummus and wholemeal bread, beans and corn
- ●Cereals + oilseeds: wholemeal bread and almond butter, quinoa and pumpkin seeds
Current recommendations recommend diversifying protein sources and moving towards a better balance between animal and plant proteins, from a perspective of both individual health and environmental sustainability (EAT-Lancet report, 2019).
4. The best food sources of protein
5. Can you eat too much protein?
This is a legitimate question, especially for people who follow high-protein diets or consume protein supplements. Here is what the scientific literature indicates:
- ●In a healthy adult with normal kidney function, a high protein intake (up to 2 g/kg/day) does not present a demonstrated short-term risk.
- ●On the other hand, in people suffering from chronic kidney failure, excess protein can worsen the disease. Medical follow-up is essential in this case.
- ●A diet very rich in animal proteins (particularly red meat and cold meats) is associated, in the long term, with an increased risk of certain digestive cancers according to the IARC (International Agency for Research on Cancer).
The key remains balance: neither deficit nor excess, and diversification of sources to cover all essential amino acids throughout the day.
💡 tips to remember
- My basic protein requirement is approximately 0.83 g per kilogram of body weight per day, or approximately 58 g for a 70 kg sedentary person.
- I diversify my sources: alternating animal and plant proteins is the best strategy to cover all my essential amino acids.
- I combine legumes and cereals to obtain a profile complete protein from plant sources only.
- The majority of French people cover their needs without protein supplements: there is no need to take them unless there is a specific medical or sporting indication.
- As I age, my needs increase slightly: after 65 years, aiming for 1 to 1.2 g/kg/day helps preserve muscle mass and prevent sarcopenia.
- I limit excess red meat and cold meats: beyond 500 g of red meat per week, the risk of colorectal cancer increases according to the IARC.
