The standard reference is 0.8g per kilogram of body weight per day — the floor required to prevent deficiency in an inactive adult. Most current research, including position statements from the American College of Sports Medicine and the International Society of Sports Nutrition, suggests substantially more for active individuals: 1.4–2.0g/kg for endurance athletes and resistance trainers, and 1.0–1.2g/kg for older adults specifically to combat age-related muscle loss.
For a 70kg (155 lb) adult, that puts the practical range at roughly 70g (sedentary) to 140g (very active or building muscle) per day. The good news is that hitting these targets is straightforward once you know which foods deliver the most protein per calorie.
Animal Proteins
Animal sources provide complete proteins — containing all nine essential amino acids in proportions the body can readily use. They are the most efficient option for hitting high protein targets:
- Chicken breast — 31g per 100g cooked
- Tuna — 25g per 100g
- Turkey breast — 29g per 100g cooked
- Lean beef (sirloin, tenderloin) — 26g per 100g cooked
- Salmon — 22g per 100g cooked
- Greek yoghurt (plain, full-fat) — 10g per 100g
- Cottage cheese — 11g per 100g
- Eggs — 6g per large egg
Plant Proteins
Plant proteins are generally lower in concentration than animal sources but offer fibre and other nutrients in the same package. Most plant proteins are incomplete on their own but provide complete profiles when varied across the day:
- Lentils — 18g per cup cooked
- Black beans — 15g per cup cooked
- Chickpeas — 15g per cup cooked
- Tofu (firm) — 17g per 100g
- Tempeh — 19g per 100g
- Edamame — 18g per cup
- Quinoa — 8g per cup cooked (and one of the few plant complete proteins)
- Hemp seeds — 9g per 3 tablespoons
Dairy and Eggs
Dairy and eggs are some of the most cost-effective protein sources by gram of protein per dollar:
- Whey protein powder — 24g per scoop (most concentrated source available)
- Greek yoghurt — 10-20g per cup depending on brand
- Cottage cheese — 25g per cup
- Milk — 8g per cup
- Eggs — 6g per egg
Protein Distribution Matters as Much as Total Intake
Research consistently shows that distributing protein roughly evenly across three or four meals per day is more effective for muscle protein synthesis than the same total amount eaten mostly at dinner. Aim for 25–40g of protein per meal as a practical target, scaled to your overall daily intake and body weight.
For older adults in particular, hitting a per-meal threshold of around 30g of protein appears to be important — below that level, the muscle synthesis response is muted regardless of total daily intake.
How Much Protein Do You Actually Need?
Practical guidance by goal:
- Sedentary adult, general health: 0.8g/kg body weight (around 55g for a 70kg adult)
- Regular exerciser: 1.2–1.6g/kg (84–112g for a 70kg adult)
- Building muscle: 1.6–2.2g/kg (112–154g for a 70kg adult)
- Older adult (60+): 1.0–1.2g/kg, with attention to per-meal distribution
- Weight loss while preserving muscle: 1.6–2.4g/kg of target body weight
Most people who track their intake for the first time discover they are eating much less protein than they assumed. A small adjustment — adding a serving of Greek yoghurt, a few extra eggs, or a scoop of whey protein each day — is often enough to close the gap.
References
- American College of Sports Medicine — Protein Intake for Muscle Maintenance — Professional society protein recommendations
- Jäger et al. (2017) — ISSN Position Stand: Protein and Exercise — International Society of Sports Nutrition consensus statement
- Mayo Clinic — Are you getting enough protein? — Clinical guidance on protein intake
- Harvard T.H. Chan — Protein — Evidence-based overview of protein in the diet
- Dietary Guidelines for Americans 2020-2025 — Federal protein intake guidelines
- USDA FoodData Central — Reference database for nutrient content of foods