Ask ten people how much protein to build muscle and you will get ten answers, most of them louder than they are accurate. The good news is that this question has been studied carefully for about two decades, and the research points to a fairly narrow range. Here is what the numbers say, why the government's recommendation is lower than what lifters need, and how to hit your target with normal food from a normal grocery store.
The RDA is a floor, not a goal
The Recommended Dietary Allowance for protein is 0.8 grams per kilogram of body weight per day. For a 165 pound person (75 kg) that works out to about 60 grams.
That number was set to prevent deficiency in sedentary adults. It was never meant to describe the amount that helps you add muscle while you train hard three or four days a week. Stuart Phillips, one of the most published researchers in this field, has argued for years that athletes and regular lifters sit well above the RDA because training raises the rate at which muscle tissue is broken down and rebuilt.
How much protein to build muscle: the research range
The most useful single study here is a 2018 meta-analysis in the British Journal of Sports Medicine led by Robert Morton. It pooled 49 trials with 1,863 people who were lifting weights, and asked at what point extra protein stopped adding extra muscle.
The breakpoint landed at 1.62 grams per kilogram per day. Above that, the gains in lean mass flattened out. The confidence interval stretched up to about 2.2 g/kg, which is why you often see the range quoted as 1.6 to 2.2.
That lines up closely with the International Society of Sports Nutrition's 2017 position stand, which recommends 1.4 to 2.0 g/kg per day for people who train, with the higher end for those who are dieting or training very hard.
In plain terms, for our 75 kg lifter:
- Solid target: about 120 grams a day (1.6 g/kg)
- Upper end, useful during a fat loss phase: up to about 165 grams a day (2.2 g/kg)
If you carry a lot of body fat, base the math on your goal weight rather than your current weight. The protein is for the muscle you have and want to keep, not the tissue you are trying to lose.
Spread it across the day
Total daily intake matters most, but how you divide it matters too. Muscle protein synthesis, the process that actually builds new tissue, is switched on by each protein-containing meal and then returns to baseline a few hours later.
Classic dose-response work from Daniel Moore and colleagues in 2009 found that in young men, around 20 grams of high quality protein after training was enough to maximize that response. Later work scaled this to body size. A 2018 review by Brad Schoenfeld and Alan Aragon suggests about 0.4 g/kg per meal, spread over at least four meals, as a practical way to hit roughly 1.6 g/kg for the day. For a 75 kg person, that is about 30 grams per meal.
Older adults need a bigger dose per meal
Muscle becomes less responsive to protein with age, a phenomenon called anabolic resistance. Moore's 2015 follow-up study showed that older men needed roughly 0.4 g/kg per meal to get the same response that younger men got from about 0.24 g/kg. If you are past 60, aim for 35 to 40 grams at each main meal rather than nibbling 15 grams here and there.
The anabolic window is mostly a myth
You have probably heard that you need a shake within 30 minutes of your last set or the workout is wasted. A 2013 meta-analysis from Schoenfeld, Aragon and Krieger looked directly at this. Once they controlled for total daily protein, the timing of the post-workout dose made no meaningful difference to strength or muscle size.
The window is real, but it is wide. If you ate a protein-rich meal within a couple of hours before training, you have several hours after to eat again. The habit that pays off is simply not skipping meals on training days.
Our coaches walk through exactly this kind of planning with new clients, so if you want someone to look at your actual week and your actual fridge, you can book a free consult.
Is more always better?
Past about 2.2 g/kg the data stop showing extra muscle. Extra protein beyond that is not harmful for most people, but it is expensive and it displaces carbohydrate and fat that fuel your training. Diminishing returns set in fast.
The kidney concern comes up a lot. A 2018 meta-analysis in the Journal of Nutrition by Michaela Devries and colleagues pooled 28 randomized trials and found that higher protein intakes did not harm kidney function in healthy adults. The small rise in filtration rate they saw is a normal adaptation, not damage.
One honest caveat: if you have diagnosed kidney disease or have been told to watch your protein, follow your physician's numbers rather than these.
A sample day at 120 grams, built from real food
Here is what 1.6 g/kg looks like for a 165 pound lifter using standard US portions. Protein numbers are approximate and rounded.
- Breakfast (32 g): 3 whole eggs (about 18 g) scrambled, with half a cup of 2% cottage cheese on the side (about 14 g), plus toast and fruit.
- Lunch (38 g): 5 oz grilled chicken breast (about 38 g) over rice and whatever vegetables you have.
- Snack (20 g): 1 cup plain Greek yogurt (about 17 g) with a small handful of almonds (about 3 g).
- Dinner (31 g): 4 oz lean ground beef (about 26 g) in tacos with half a cup of black beans (about 4 g) and cheese (about 1 g per tablespoon).
That lands around 121 grams without a single scoop of powder. Swap in salmon, pork loin, turkey, tofu or shrimp as you like. The pattern is the point: one obvious protein source at each of four meals.
A simple way to check your numbers
Weigh your most common proteins once with a kitchen scale so you learn what 4 or 5 ounces looks like on your plate. After a week you will not need the scale.
Notes for plant-based lifters
You can build muscle on a plant-based diet. Two adjustments help. First, aim for the upper half of the range, closer to 2.0 g/kg, because plant proteins are digested a little less completely and most are lower in the amino acid leucine, which is the main trigger for muscle protein synthesis.
Second, lean on the densest sources: tofu, tempeh, seitan, lentils, edamame and a soy or pea protein powder. Mixing sources through the day, grains with legumes for example, covers the full amino acid profile without any special meal pairing rules.
When a protein supplement makes sense
Powder is food in a convenient form, nothing more. It earns a place in your kitchen when:
- You consistently fall 20 to 40 grams short of your target with meals alone.
- Your schedule leaves a six or seven hour gap between meals and a shake is the realistic fix.
- You train early and cannot stomach a full breakfast first.
- You are plant-based and struggling to reach the higher end of the range.
Whey, casein, soy and pea blends all work. Pick one you will actually drink, check that it has roughly 20 to 25 grams per serving, and treat it as a gap filler rather than the foundation.
Your checklist for this week
- Multiply your body weight in pounds by 0.73 to get your daily protein target in grams. That is the 1.6 g/kg number.
- Divide by four. That is your per-meal target.
- Pick one protein anchor for each of four meals and write them on the fridge.
- Stop worrying about the clock after training. Eat your next meal when you are hungry, within a few hours.
- Reassess in four weeks. If you are recovering well and getting stronger, the number is working.
Keep going with Sonder
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Sources
- Morton RW, et al. (2018). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine. https://pubmed.ncbi.nlm.nih.gov/28698222/
- Jäger R, et al. (2017). International Society of Sports Nutrition position stand: protein and exercise. Journal of the International Society of Sports Nutrition. https://pubmed.ncbi.nlm.nih.gov/28642676/
- Phillips SM. (2012). Dietary protein requirements and adaptive advantages in athletes. British Journal of Nutrition. https://pubmed.ncbi.nlm.nih.gov/23107527/
- Schoenfeld BJ, Aragon AA. (2018). How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution. Journal of the International Society of Sports Nutrition. https://pubmed.ncbi.nlm.nih.gov/29497353/
- Moore DR, et al. (2009). Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. American Journal of Clinical Nutrition. https://pubmed.ncbi.nlm.nih.gov/19056590/
- Moore DR, et al. (2015). Protein ingestion to stimulate myofibrillar protein synthesis requires greater relative protein intakes in healthy older versus younger men. Journals of Gerontology: Series A. https://pubmed.ncbi.nlm.nih.gov/25056502/
- Schoenfeld BJ, Aragon AA, Krieger JW. (2013). The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. Journal of the International Society of Sports Nutrition. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3879660/
- Devries MC, et al. (2018). Changes in kidney function do not differ between healthy adults consuming higher- compared with lower- or normal-protein diets: a systematic review and meta-analysis. Journal of Nutrition. https://pmc.ncbi.nlm.nih.gov/articles/PMC6236074/
