From the Guidelines
The recommended protein intake is 0.8 grams of protein per kilogram of body weight for sedentary adults, which translates to about 0.36 grams per pound, but can vary based on individual factors such as physical activity level, age, and health status, with higher intakes recommended for athletes, older adults, and those with certain medical conditions, as supported by the most recent study 1.
Protein Intake Recommendations
The following are general guidelines for protein intake:
- Sedentary adults: 0.8 g/kg (0.36 g/lb) of body weight
- Physically active adults: 1.1-1.4 g/kg (0.5-0.64 g/lb) of body weight
- Athletes: 1.2-2.0 g/kg (0.55-0.9 g/lb) of body weight
- Older adults: 1.2-1.5 g/kg (0.55-0.68 g/lb) of body weight
- Pregnant or lactating women: 1.1-1.3 g/kg (0.5-0.59 g/lb) of body weight
Calculating Protein Needs
To calculate individual protein needs, multiply body weight in kilograms by the appropriate factor for activity level, as supported by 1 and 1.
Spreading Protein Intake
Spreading protein intake throughout the day in servings of 20-30 grams per meal can optimize muscle protein synthesis and help maintain satiety, as suggested by 1 and 1.
Special Considerations
Certain medical conditions, such as chronic kidney disease, may require adjusted protein intake, with recommendations ranging from 0.6-1.5 g/kg (0.27-0.68 g/lb) of body weight, as supported by 1 and 1.
From the Research
Recommended Protein Intake Chart for Body Weight
The recommended protein intake varies based on factors such as age, sex, weight, and activity level. According to the studies, here are some general guidelines:
- For a healthy adult with minimal physical activity, the recommended dietary allowance is 0.8 g protein per kg body weight per day 2
- For individuals with moderate physical activity, a dietary intake of 1.0-1.3 g protein per kg body weight per day is recommended 2, 3
- For individuals with intense physical activity, a dietary intake of 1.6 g protein per kg body weight per day is recommended 2
- For athletes, a higher protein intake of at least 1.2-1.6 g/kg/day is recommended to maximize athletic performance 3
- For weight loss and weight maintenance, a normal protein intake of 0.8 g/kg/day is required, while an elevated protein intake of 1.2 g/kg/day is necessary for additional preservation of resting energy expenditure and fat-free mass 4
Protein Intake Units
The units of protein intake can affect the interpretation of its health effects. The studies suggest that:
- Units expressed in body weight (e.g., g/kg) can be confounded by body weight, irrespective of outcome 5
- Units expressed in grams, percent energy, and ideal body weight show similar results, with or without adjustment for body size 5
- The use of WHO (g/kg ideal body weight) compared with US (g/kg actual body weight) units should be specified, and ideally, gram or percent energy should be used in observational studies 5
Safety and Upper Limits
The studies also provide information on the safety and upper limits of protein intake:
- Long-term consumption of protein at 2 g per kg body weight per day is safe for healthy adults 2
- The tolerable upper limit is 3.5 g per kg body weight per day for well-adapted subjects 2
- Chronic high protein intake (>2 g per kg body weight per day for adults) may result in digestive, renal, and vascular abnormalities and should be avoided 2