How to Calculate Your Protein Needs: The Complete Guide
Calculate your individual protein needs: scientific foundations, evidence-based recommendations, calculation by body weight and activity level, best protein sources.
Why Protein Matters So Much
Proteins are the building blocks of life. Every cell, every enzyme, every hormone, every antibody — all consist of amino acids, the building blocks of proteins. In the body, proteins fulfill fundamental functions:
- Structural proteins: Collagen (connective tissue, bones), keratin (hair, nails)
- Enzymes: Catalysis of all biochemical reactions
- Hormones: Insulin, glucagon, growth hormone
- Immune proteins: Antibodies, immunoglobulins
- Transport proteins: Hemoglobin (O₂), albumin (fatty acids, hormones)
- Contractile proteins: Actin and myosin (muscle function)
Amino Acids: Essential vs. Non-Essential
Of the 20 proteinogenic amino acids, 9 are essential — the body cannot synthesize them: Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, Valine.
Branched-Chain Amino Acids (BCAAs) — Leucine, Isoleucine, Valine — play a key role in muscle building: Leucine directly activates the mTOR signaling pathway (protein synthesis initiator).
Biological Value: Not All Proteins Are Equal
The biological value (BV) indicates how efficiently dietary protein is converted into body protein (reference: whole egg = 100):
| Food | Biological Value | |---|---| | Whole egg | 100 | | Milk | 88 | | Beef | 80 | | Fish | 83 | | Soy | 86 | | Potato | 76 | | Wheat | 54 |
Protein complementation: Combining legumes + grains (e.g., rice + beans) raises the biological value above 100, since missing amino acids are complemented.
How Much Protein Do You Need? — The Calculation
Evidence-Based Daily Requirements:
- Adults (18–65 years): 0.8 g protein / kg body weight / day
- Seniors (> 65 years): 1.0–1.2 g/kg/day (due to reduced protein synthesis: sarcopenia prevention)
- Pregnant women: +10 g/day in 2nd and 3rd trimester
- Breastfeeding women: +15–20 g/day
Increased Needs:
| Situation | Recommended Intake | |---|---| | Endurance sports | 1.2–1.6 g/kg/day | | Strength training (muscle building) | 1.6–2.2 g/kg/day | | Weight loss (preserving muscle mass) | 1.6–2.4 g/kg/day | | Injury / recovery | 1.5–2.0 g/kg/day | | Seniors with sarcopenia | 1.5–2.0 g/kg/day |
Calculation Example:
75 kg, moderate strength training (3×/week):
- Requirement: 75 kg × 1.8 g = 135 g protein/day
- Distribution: 3 main meals of 35–40 g + 1 snack of 20 g
Protein Timing: When to Eat?
- Post-workout: 20–40 g protein within 1–2 hours optimizes muscle protein synthesis (anabolic window)
- Before sleep: Casein (cottage cheese, quark) — slowly digestible, supplies muscles overnight
- Breakfast: At least 20–30 g protein prevents muscle catabolism (cortisol peak in the morning)
Best Protein Sources
Animal:
- Low-fat quark/cottage cheese: 13 g/100 g
- Chicken breast: 23 g/100 g
- Salmon: 20 g/100 g
- Eggs: 13 g/100 g (+ perfect amino acid profile)
Plant-based:
- Lupin flour: 38 g/100 g
- Soybeans: 36 g/100 g
- Lentils (dried): 26 g/100 g
- Edamame: 11 g/100 g
Safety: Is Too Much Protein Harmful?
With healthy kidneys, protein intake up to 2.2 g/kg/day is well tolerated. With pre-existing kidney insufficiency, protein restriction (< 0.8 g/kg/day) is indicated — please consult a physician.
Conclusion
Protein is not a trend — it is biochemical necessity. Nutrion calculates your individual protein needs based on weight, activity level and health goals, and shows you how to efficiently achieve them.