How Much Protein Per Day to Build Muscle? Exact Grams by Bodyweight

You've heard "1 gram per pound of bodyweight," but is that right? Does more help? Will it wreck your kidneys? Is 30 grams really the per-meal absorption ceiling? Few topics in fitness nutrition collect more myth and marketing than protein. This guide pulls from Morton et al. (2018) (a 49-study meta-analysis), Helms et al. (2014) on natural bodybuilding, and Schoenfeld and Aragon (2018) on protein distribution to give you the actual gram-level answer for your bodyweight, your goal, and your training intensity. We also cover per-meal targets, animal versus plant sources, and how to verify the effect on your training output.

The science behind muscle protein recommendations

The starting point is the Morton et al. (2018) meta-analysis of 49 studies and 1,863 participants. It concluded that hypertrophic benefit from extra protein plateaus around 1.6 g per kg of bodyweight, with the upper bound of the 95% confidence interval at 2.2 g per kg. For a 70 kg adult that means 112-154 g per day is the optimal hypertrophy range.

Eating more isn't harmful but adds little extra muscle. Three contexts shift the target up. First, during a fat-loss phase: Helms et al. (2014) recommend 2.3-3.1 g per kg in lean dieters to preserve muscle. Second, older adults: anabolic resistance after age 50 means more protein is needed for the same MPS response. Third, high-volume training blocks: when training stress spikes, sit at the upper end of the range to support recovery.

Despite the persistent claim, high-protein diets do not damage healthy kidneys. Devries et al. (2018) found that intakes above 2.0 g per kg do not produce clinically meaningful changes in glomerular filtration rate in healthy adults.

Exact intake by bodyweight and goal

The table below converts the science into grams per day for common bodyweights and goals. If your body fat is high (men 25%+, women 32%+) calculate from lean body mass instead of total weight.

So a 75 kg lifter targeting hypertrophy lands around 120-150 g per day; cutting pushes that up to 180 g to minimize muscle loss. Track your training output alongside intake changes to find your personal sweet spot. Pairing this with an objective output measure like an autoregulated velocity model makes it easier to see whether nutrition tweaks actually move the needle.

How much per meal? Distribution matters

Total daily intake matters most, but distribution still moves the needle. Schoenfeld and Aragon (2018) concluded that maximal MPS is best supported by roughly 0.4 g per kg per meal across about 4 meals. For a 75 kg lifter that's ~30 g per meal, ~120 g over four feeds. This contradicts the "30 g cap" myth: MPS does plateau around 30 g, but the rest of the protein is still used for other metabolic needs.

Res et al. (2012) showed that ~40 g of casein before sleep raises overnight MPS by about 22%. Worth trying when training stress is high or recovery feels low. Recovery itself can be tracked objectively with daily countermovement jump variability.

Protein sources: animal vs plant quality

Two factors define protein quality: essential amino acid profile and digestibility. Leucine is the direct trigger of mTOR signaling, and ~2.5-3 g of leucine per meal is needed to maximally stimulate MPS. Animal proteins run 8-11% leucine; plants are 6-8%.

Plant-forward diets can absolutely build muscle but need two adjustments: 10-15% more total grams (digestibility correction) and a mix of legumes, grains, and nuts for complete amino acid coverage. Hevia-Larrain et al. (2021) found vegan lifters built muscle equivalently to omnivores when total protein and training stimulus matched.

Sample diets and common mistakes

Sample day for a 75 kg lifter targeting 150 g of protein.

Five common mistakes: 1) hitting the daily total but stuffing it into one meal (MPS still saturates around 30-40 g); 2) skipping breakfast and gorging at dinner (low overnight MPS, poor morning recovery); 3) relying on processed meats (high saturated fat and sodium); 4) extreme low-carb dieting, which forces protein into energy substrate use and lowers anabolic efficiency; 5) holding intake constant across very different training intensities. Track your own response with objective markers like RSI or weekly mean velocity at a fixed load.