Protein Intake Guide
Most Americans consume adequate protein but distribute it poorly — large amounts at dinner, very little at breakfast. Research shows muscle protein synthesis is maximized at 20–40g of high-quality protein per meal, with diminishing returns above that threshold.
How Much Protein You Need
Sedentary adults: 0.8g/kg body weight (RDA). Active adults: 1.2–1.6g/kg. Muscle building: 1.6–2.2g/kg. Weight loss with muscle preservation: 1.8–2.4g/kg (higher intake during deficit offsets catabolism). For a 180-lb (82kg) person building muscle: 131–180g/day.
Complete vs Incomplete Proteins
Complete proteins contain all 9 essential amino acids in sufficient quantities: animal proteins (meat, fish, eggs, dairy) and some plant sources (soy, quinoa). Incomplete proteins (most plant sources) lack one or more essential amino acids. Plant-based dieters should combine sources — rice and beans together form a complete amino acid profile.
Timing
Distributing protein evenly across 3–4 meals (30–40g each) maximizes muscle protein synthesis versus consuming most protein in one meal. Pre-sleep protein (30–40g casein or cottage cheese) extends overnight muscle protein synthesis, adding ~11% more muscle gains over 12 weeks (Maastricht University, 2012).