To build muscle, aim for 1.6–2.2 grams of protein per kilogram of body weight per day (or about 0.7–1.0 grams per pound), spread across meals in doses of 20–40 grams each. This range is supported by a 2022 systematic review and meta-analysis showing that higher protein intakes lead to small but significant gains in lean body mass and lower body strength when combined with resistance training. For a 175-pound (79 kg) person, that equals roughly 126–174 grams of protein daily.

Protein provides the amino acids needed to repair and build muscle tissue after exercise. While the Recommended Dietary Allowance (RDA) of 0.8 g/kg/day prevents deficiency, it is insufficient for maximizing muscle growth. Research consistently shows that intakes above the RDA enhance muscle protein synthesis and strength gains, especially in those engaged in resistance training.

Optimal Daily Protein Intake for Muscle Gain

The most comprehensive evidence comes from a 2022 meta-analysis of 82 randomized controlled trials published in the British Journal of Sports Medicine. Researchers found that increasing protein intake beyond habitual levels resulted in small additional gains in lean body mass and lower body muscle strength in healthy adults performing resistance exercise. The benefits plateaued around 1.6 g/kg/day, with no further advantages beyond 2.2 g/kg/day for most individuals.

For practical purposes, a target of 1.6–2.2 g/kg/day is widely recommended by sports nutrition experts. This translates to: For related context, see our guide to How Much Creatine Should You Take a Day.

  • 0.7–1.0 grams per pound of body weight
  • For a 150 lb (68 kg) person: 109–150 grams per day
  • For a 175 lb (79 kg) person: 126–174 grams per day
  • For a 200 lb (91 kg) person: 145–200 grams per day

These figures assume a goal of maximizing muscle hypertrophy. If you are in a calorie deficit to lose fat while preserving muscle, aiming for the higher end of the range (up to 2.2 g/kg/day) may be beneficial. Conversely, if you are a beginner or have a higher body fat percentage, the lower end may suffice.

Per-Meal Protein Distribution Matters

Total daily intake is the most critical factor, but how you distribute protein across meals also influences muscle protein synthesis (MPS). Research indicates that consuming 20–40 grams of high-quality protein per meal maximally stimulates MPS in young adults. This is often referred to as the "leucine threshold"—leucine is an amino acid that acts as a key trigger for muscle building.

A 2018 review in Nutrients concluded that ~0.3 g/kg per meal (about 20–30 grams for most people) is sufficient to maximally stimulate MPS after a meal. Consuming more than 40 grams in a single sitting does not further increase MPS and may lead to excess calories being oxidized or stored as fat.

For optimal results, aim for 3–5 protein-rich meals or snacks spaced evenly throughout the day, each providing 20–40 grams of protein. For example, a 175 lb person targeting 150 grams daily could have:

  • Breakfast: 30 g (e.g., 3 eggs + Greek yogurt)
  • Lunch: 40 g (e.g., chicken breast salad)
  • Post-workout shake: 25 g (whey protein)
  • Dinner: 40 g (e.g., salmon with quinoa)
  • Evening snack: 15 g (cottage cheese)

This pattern ensures repeated spikes in MPS throughout the day, which is more effective than consuming most protein in one large meal.

Protein Quality and Sources

Not all proteins are equal. High-quality proteins contain all nine essential amino acids in sufficient amounts, particularly leucine. Animal-based proteins (whey, eggs, meat, fish, dairy) are generally superior for muscle building due to their amino acid profile and digestibility. Plant-based proteins can be effective but often require combining sources (e.g., rice and pea) to achieve a complete amino acid profile.

Whey protein is often considered the gold standard because it is rapidly digested and rich in leucine. However, research shows that rice and pea protein can stimulate muscle growth similarly to whey when consumed in adequate amounts. For vegans or those with dairy allergies, plant-based protein powders are a viable alternative.

Whole foods should be prioritized because they provide additional nutrients like vitamins, minerals, and fiber. Common high-protein foods include:

  • Chicken breast (30 g per 3 oz)
  • Greek yogurt (17 g per 6 oz)
  • Eggs (6 g per large egg)
  • Lentils (9 g per half-cup cooked)
  • Tofu (10 g per half-cup)
  • Salmon (22 g per 3 oz)

Protein powders are convenient but unnecessary for most people. They are useful for those who struggle to meet protein needs through food alone, such as older adults with poor appetite or athletes with high requirements. When choosing a powder, look for third-party testing (e.g., NSF Certified for Sport) to ensure purity and label accuracy.

Special Considerations: Age, Training Status, and Health

Protein needs vary based on individual factors:

  • Older adults: Aging is associated with anabolic resistance, meaning higher protein intakes (1.2–2.0 g/kg/day) and per-meal doses of 30–40 grams may be needed to stimulate muscle protein synthesis effectively.
  • Beginners vs. advanced lifters: Beginners often experience rapid gains with moderate protein intakes, while advanced lifters may need higher intakes to continue progressing.
  • Calorie deficit: When cutting calories to lose fat, higher protein (up to 2.2 g/kg/day) helps preserve lean mass and increase satiety.
  • Kidney disease: Individuals with chronic kidney disease should consult a healthcare provider, as high protein intakes may exacerbate kidney function decline.
  • Pregnancy: Pregnant women have slightly elevated protein needs but should avoid certain supplements due to potential contaminants.

It's important to note that protein alone does not build muscle; resistance training is the primary stimulus. A meta-analysis found that protein supplementation without exercise does not increase muscle mass. Therefore, combine adequate protein with a progressive resistance training program for best results.

Can You Eat Too Much Protein?

For healthy individuals, high protein intakes (up to 2.2 g/kg/day or even higher) are generally safe. The body can handle excess protein by converting it to glucose or fat, though this may displace other nutrients. However, extremely high intakes (over 3 g/kg/day) offer no additional muscle-building benefit and may lead to gastrointestinal distress, dehydration, or increased calcium excretion.

Concerns about protein damaging kidneys in healthy people are unfounded; studies show no adverse effects on renal function in those without pre-existing kidney disease. However, if you have kidney issues, consult a doctor before increasing protein.

In summary, for muscle gain, target 1.6–2.2 g/kg/day, distribute protein evenly across meals, prioritize high-quality sources, and pair with resistance training. Most people can meet needs through food, but supplements can help fill gaps.

Sources

  • Systematic review and meta‐analysis of protein intake ... - PMC
  • Recent Perspectives Regarding the Role of Dietary Protein for ...
  • Dietary Protein and Muscle Mass: Translating Science ... - PMC