Find out exactly how much protein you need per day.
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The short answer: more than most people think. General guidelines (0.8g/kg) are set for basic health, not for people who exercise. If you train regularly or want to change your body composition, the evidence-based target is much higher.
Research consistently shows that 1.6–2.4g of protein per kg of body weight is optimal for active adults. The exact amount depends on your goal:
Higher protein (2.0–2.4g/kg) during a calorie deficit preserves muscle mass. Protein is also the most filling macro, so you eat less without trying.
1.6–2.0g/kg keeps you in positive nitrogen balance — the state where muscle protein synthesis matches breakdown. Good for long-term body composition.
1.6–2.2g/kg gives your body the building blocks for muscle protein synthesis. More protein beyond 2.2g/kg shows diminishing returns for most people.
Athletes and those with physical jobs need the upper end of the range. Higher activity = more muscle breakdown = more protein needed to recover and rebuild.
Protein is the only macro your body can use to build and repair muscle tissue. Carbs and fat provide energy — protein provides structure. Every meal you eat is an opportunity to either support or undermine your muscle mass.
During fat loss, this matters even more. In a calorie deficit your body will break down both fat and muscle for energy unless you give it enough protein to protect the muscle. Studies show that people eating adequate protein during fat loss retain significantly more lean mass than those eating too little — even on the same calorie deficit.
For muscle gain, protein timing matters too. Spreading your intake evenly across 3–4 meals maximises muscle protein synthesis throughout the day, compared to eating most of your protein in one sitting.
Not all protein is equal. Animal sources are “complete” proteins (all 9 essential amino acids), while most plant sources are incomplete. High-quality sources per 100g:
The biggest challenge isn’t knowing your protein target — it’s building meals that consistently hit it. A few practical strategies:
PrepSmart generates a full 7-day meal plan matched to your protein target, calorie goal, and budget. Every recipe has full macros so you always know exactly what you’re eating.
For sedentary adults, 0.8g of protein per kg of body weight is the minimum for basic health. For active adults who exercise regularly, the evidence-based target is 1.6–2.4g per kg. If you are trying to build muscle or lose fat while preserving muscle mass, aim for at least 1.6g per kg of body weight per day.
For most healthy adults, high protein intake is safe. Studies show intakes up to 3g per kg per day are tolerated without harm. The practical concern is that very high protein intake crowds out carbs and fats, which can reduce energy levels and training performance. Stick to 1.6–2.4g per kg unless you have specific athletic reasons to go higher.
The best protein sources per gram include chicken breast (~31g/100g), canned tuna (~25g/100g), Greek yogurt (~10g/100g), eggs (~13g/100g), and cottage cheese (~11g/100g). For plant-based options, tofu (~8g/100g), edamame (~11g/100g), and lentils (~9g/100g cooked) are strong choices. Combining multiple sources across meals ensures you hit your daily target without relying on a single food.