Protein is the most important macronutrient for body composition. Whether your goal is fat loss, muscle gain, or healthy ageing, getting the right amount of protein is critical — and most people either under-eat or drastically over-eat it.
This calculator uses your body weight and goal to determine your optimal protein range — from the basic 0.8 g/kg minimum for sedentary adults up to 2.2 g/kg for those maximising muscle hypertrophy.
The Evidence for Protein Recommendations
The RDA of 0.8 g/kg was established to prevent deficiency, not to optimise health. For active individuals, research consistently supports 1.2–2.2 g/kg. A landmark 2017 meta-analysis (Morton et al.) found that protein intakes above 1.62 g/kg provided no additional muscle-building benefit — though 2.2 g/kg is recommended as a safe upper target.
Protein Timing and Distribution
Total daily protein matters most. However, distributing protein across 3–5 meals of 20–40g each maximises muscle protein synthesis (MPS). A leucine threshold of ~2–3g per meal is needed to fully activate MPS — this requires approximately 20–30g of complete protein per meal.
Complete vs Incomplete Proteins
Complete proteins contain all 9 essential amino acids and are found in animal products (meat, fish, eggs, dairy) and some plant sources (soy, quinoa). Plant proteins are generally incomplete — vegans should combine sources (rice + legumes) or use fortified foods and supplements to ensure adequate essential amino acid intake.
High Protein Foods Reference
Top animal-based sources: chicken breast (31g/100g), tuna (30g/100g), beef mince (26g/100g), salmon (25g/100g), eggs (13g/100g), Greek yoghurt (10–17g/100g), cottage cheese (11g/100g). Top plant sources: tofu (8g/100g), lentils (9g/100g cooked), chickpeas (9g/100g cooked), edamame (11g/100g). Whey protein (25g/30g serving) is a convenient supplement.
💡 Expert Tips
- ✓Prioritise whole food protein sources — they provide satiety and micronutrients that protein supplements lack.
- ✓Eat 20–40g of protein at each meal to fully stimulate muscle protein synthesis — spreading intake is more effective than one or two large servings.
- ✓Leucine is the key amino acid that triggers MPS — dairy, eggs, and meat are particularly rich in leucine.
- ✓Protein has the highest thermic effect of food (20–30% of calories burned in digestion) — high-protein diets have a metabolic advantage.
- ✓Protein reduces ghrelin (hunger hormone) and increases satiety hormones — prioritising protein makes calorie deficits much easier to maintain.
📊 Protein Requirements by Goal
| Goal | Protein (g/kg) | 75 kg example | Priority foods |
|---|---|---|---|
| Sedentary adult | 0.8 g/kg | 60 g/day | Any complete protein |
| Active adult | 1.2–1.6 g/kg | 90–120 g/day | Lean meats, dairy, eggs |
| Fat loss | 1.8–2.2 g/kg | 135–165 g/day | Chicken, fish, Greek yoghurt |
| Muscle gain | 1.6–2.2 g/kg | 120–165 g/day | Beef, whey, eggs, dairy |
| Endurance | 1.2–1.6 g/kg | 90–120 g/day | Varied protein sources |
| Healthy ageing 55+ | 1.2–1.6 g/kg | 90–120 g/day | High leucine: dairy, eggs |