To gain muscle, most people need between 1.6 and 2.2 grams of protein per kilogram of body weight each day. For a 180-pound (82 kg) person, that works out to roughly 130 to 180 grams of protein daily. This range comes from decades of research on resistance-trained individuals and represents the point where muscle growth is maximized without meaningful additional benefit from eating more.
The Evidence-Based Range
Multiple reviews from sports nutrition researchers converge on the same window: 1.4 to 2.0 g/kg/day, with most placing the sweet spot at 1.6 to 1.8 g/kg/day. The International Society of Sports Nutrition recommends 1.4 to 2.0 g/kg/day for individuals engaged in resistance training. If you want a single number to aim for, 1.6 g/kg/day is the floor for maximizing muscle growth, and going up to 2.2 g/kg/day provides an extra margin of safety.
In pounds, the simplest rule of thumb is 0.7 to 1.0 grams per pound of body weight. Here’s what that looks like for different body sizes:
- 140 lbs (64 kg): 100–140 g protein per day
- 160 lbs (73 kg): 115–160 g per day
- 180 lbs (82 kg): 130–180 g per day
- 200 lbs (91 kg): 145–200 g per day
- 220 lbs (100 kg): 160–220 g per day
If you carry a significant amount of body fat, base your calculation on your goal body weight or lean body mass rather than your total weight. A 250-pound person at 35% body fat doesn’t need 250 grams of protein.
How to Spread It Across Meals
Hitting your daily total matters most, but how you distribute it across meals also plays a role. Research suggests aiming for about 0.4 g/kg per meal across at least four meals. For a 180-pound person, that’s roughly 30 to 40 grams of protein per sitting. The upper end of this range is about 0.55 g/kg per meal, or around 45 grams for the same person.
This matters because each time you eat a protein-rich meal, your body ramps up muscle protein synthesis for a few hours before it tapers off. Eating all your protein in one or two large meals means you miss opportunities to trigger that process throughout the day. Four meals spaced three to five hours apart is a practical target for most people.
The Post-Workout Window Is Flexible
The idea that you need to chug a protein shake within 30 minutes of your last set is overstated. If you ate a solid meal containing protein one to two hours before training, the amino acids from that food are still circulating in your bloodstream during and after your workout. In that scenario, your next regular meal (whether it’s immediately after or an hour or two later) is sufficient.
The timing becomes more important if you train fasted or haven’t eaten in more than three to four hours. In that case, consuming at least 25 grams of protein soon after training helps shift your body from a catabolic to an anabolic state. A practical guideline: don’t let your pre-workout and post-workout meals be separated by more than three to four hours, accounting for your training time in between. If those meals are large and mixed with fats and carbs (which slow digestion), you can stretch that window to five or six hours.
The Leucine Threshold
Not all protein is equal when it comes to triggering muscle growth. A key factor is leucine, an amino acid that acts as the “on switch” for muscle protein synthesis. You need roughly 2 to 3 grams of leucine per meal to flip that switch. A chicken breast or a scoop of whey protein easily clears this threshold. Plant proteins can too, but you typically need a larger serving since most plant sources contain less leucine per gram of protein.
Animal vs. Plant Protein Quality
Protein quality is measured by how well your body can digest and use the amino acids in a given food. On the standard scoring system (called DIAAS), animal proteins generally rank higher. Pork scores around 117, casein (the main protein in milk and cheese) about 117, and whey around 85. Among plant sources, soy ranks highest at about 91, while pea protein scores around 70 and rice protein falls lower still.
This doesn’t mean plant-based diets can’t support muscle growth. It means you need to eat a bit more total protein and combine different sources to cover all your essential amino acids. Soy and potato protein are the strongest plant options. Combining grains with legumes (rice and beans, for instance) helps fill in amino acid gaps that either source would have on its own. If you eat entirely plant-based, aiming for the higher end of the protein range (2.0 to 2.2 g/kg/day) is a smart strategy.
When You’re Cutting Body Fat
If you’re eating in a calorie deficit, your protein needs go up, not down. During a calorie deficit, your body is more likely to break down muscle tissue for energy. Higher protein intake counteracts this. Research comparing groups eating around 0.8 g/kg/day versus 1.0 g/kg/day during weight loss found that the higher-protein group lost significantly less lean body mass while shedding the same amount of fat.
Those numbers, however, were studied in non-athletes. For someone who lifts weights and is actively trying to preserve or build muscle while losing fat, the recommendation climbs higher. Aim for 2.0 to 2.4 g/kg/day during a cut. This is one of the few situations where going above the standard 1.6 to 2.2 range has a clear payoff.
Adjustments for Age
Adults over 60 face something called anabolic resistance: the same amount of protein that stimulates strong muscle growth in a 25-year-old produces a weaker response in an older body. Research shows that older adults need about 0.40 g/kg per meal to maximize muscle protein synthesis, compared to just 0.24 g/kg per meal for younger adults. That’s roughly 65% more protein per meal to get the same anabolic signal.
One study found that older men needed to increase their daily protein intake by about 0.5 g/kg above their habitual intake to see meaningful gains in muscle mass. Practically, this means older adults should aim for at least 1.6 g/kg/day and may benefit from going higher. There’s also evidence that older women require even more protein than older men to overcome anabolic resistance, making consistent high-protein meals especially important.
Beginners vs. Experienced Lifters
When you first start lifting, your body is less efficient at using dietary protein for muscle repair. Protein requirements may actually be slightly higher during the initial stages of a training program or when you sharply increase your training volume. As your body adapts over months and years, it gets better at retaining protein, which means experienced lifters may be able to maintain muscle growth at the lower end of the recommended range. Regardless of experience level, staying at or above 1.6 g/kg/day keeps you covered.
Is Too Much Protein Harmful?
For healthy people, high-protein diets have no established link to kidney damage or other medical problems. The concern about protein harming kidneys applies to people who already have kidney disease, because compromised kidneys struggle to filter the waste products of protein metabolism. If your kidneys are healthy, intakes of 2.0 to 2.2 g/kg/day are well within safe territory. Even higher intakes (up to 3.0+ g/kg/day) have been studied in resistance-trained individuals without adverse effects on kidney function, though the extra protein beyond 2.2 g/kg/day doesn’t appear to build more muscle.
What This Looks Like in Real Food
Hitting 150 or more grams of protein daily requires some intentionality. A single large egg contains about 6 grams of protein, so eggs alone won’t get you there. Here’s a rough sense of common protein counts per serving:
- Chicken breast (6 oz, cooked): ~38 g
- Ground beef, 90% lean (6 oz, cooked): ~34 g
- Salmon fillet (6 oz, cooked): ~34 g
- Greek yogurt (1 cup): ~15–20 g
- Eggs (2 large): ~12 g
- Whey protein (1 scoop): ~25 g
- Lentils (1 cup, cooked): ~18 g
- Tofu, firm (1/2 block): ~20 g
A realistic day at 160 grams might look like: three eggs and Greek yogurt at breakfast (32 g), a chicken breast with rice at lunch (38 g), a protein shake as a snack (25 g), a salmon fillet with vegetables at dinner (34 g), and a serving of cottage cheese in the evening (28 g). That totals around 157 grams without any unusual effort, just consistent inclusion of a protein source at every meal.