Most people need 1.6 to 2.2 grams of protein per kilogram of body weight per day to maximize muscle growth from resistance training. For a 180-pound (82 kg) person, that works out to roughly 130 to 180 grams of protein daily. Eating less than that range still builds muscle, but a large meta-analysis found that protein intake beyond 1.6 g/kg/day produced diminishing returns, with no statistically significant additional hypertrophy beyond 2.2 g/kg/day.
The Daily Target Range
The broad recommendation for people lifting weights is 1.2 to 2.0 g of protein per kilogram of body weight. But a breakpoint analysis across multiple studies narrowed the sweet spot: 1.6 g/kg/day is the threshold where additional protein stops meaningfully boosting muscle gains. That doesn’t mean going higher is wasteful for everyone, but it does mean that someone eating 2.5 g/kg/day probably isn’t getting more muscle than someone eating 1.8 g/kg/day, all else being equal.
To find your number, convert your weight to kilograms (divide pounds by 2.2), then multiply by 1.6 for the lower target and 2.2 for the upper end. A 150-pound person (68 kg) would aim for 109 to 150 grams per day. A 200-pound person (91 kg) would target 145 to 200 grams.
How Much Protein Per Meal
Your body can only use so much protein at once for muscle building. Research shows that about 20 to 25 grams of high-quality protein per meal (roughly 0.24 to 0.3 g/kg of body weight) maximally stimulates muscle protein synthesis in younger adults. Doubling that to 40 grams in a single sitting produced no significant additional muscle-building response in studies of younger men.
This means spreading your intake across the day matters more than hitting one massive protein meal. A practical approach: aim for at least four protein-containing meals, each with 0.4 to 0.55 g/kg of body weight. For a 180-pound person, that translates to about 30 to 45 grams per meal across four meals. This distribution helps you reach the 1.6 to 2.2 g/kg daily target while keeping each dose in the range your muscles can actually use.
Why Age Changes the Math
Older adults need more protein per meal to get the same muscle-building signal. This is sometimes called anabolic resistance: as you age, your muscles become less responsive to a given dose of protein. In one study, men in their early twenties saw a strong muscle-building response from just 20 grams of protein, while men in their early seventies showed almost no response at that same dose. The older group needed 40 grams to trigger comparable muscle protein synthesis.
If you’re over 50, aiming for about 0.4 g/kg per meal (instead of 0.2 g/kg for younger adults) helps compensate. For a 165-pound person, that’s roughly 30 grams of protein per meal as a minimum. The leucine content of your protein matters here too. Leucine is the amino acid that acts as the primary “on switch” for muscle building, and older adults need about 3 to 4 grams of leucine per meal to fully activate that signal, which corresponds to roughly 25 to 30 grams of total protein from a high-quality source.
Protein Needs During a Caloric Deficit
If you’re trying to lose fat while preserving or building muscle, you need more protein than someone eating at maintenance calories. Recommendations for athletes during weight loss range from 1.6 to 2.4 g/kg/day, with some research on resistance-trained athletes suggesting up to 2.7 g/kg/day during aggressive dieting.
The data here is striking. In one study, relatively trained but overweight young men ate 40% fewer calories than they burned. The group consuming 2.4 g/kg/day of protein actually gained lean body mass over four weeks despite that steep calorie cut. The group eating only 1.2 g/kg/day maintained their muscle but didn’t gain any. In another study with resistance-trained athletes on a similar 40% deficit, those eating just 1.0 g/kg/day lost 1.6 kg of lean mass, while those at 2.3 g/kg/day lost only 0.3 kg.
The takeaway: if you’re cutting calories, push your protein toward the higher end of the range. Going above 2.4 g/kg/day during a deficit is unlikely to provide additional muscle-sparing benefits.
Animal vs. Plant Protein Sources
Not all protein is equally effective for muscle building. Animal proteins from meat, eggs, and dairy consistently score higher in digestibility, essential amino acid content, and their ability to stimulate muscle protein synthesis. Plant proteins from sources like legumes and grains tend to be lower in leucine and sometimes lack sufficient amounts of other essential amino acids. When you eat plant protein, more of those amino acids get burned for energy rather than channeled toward building muscle.
This doesn’t mean plant-based diets can’t support muscle growth. It does mean you may need to eat a higher total amount of protein and combine different plant sources to cover all essential amino acids. If you rely heavily on plant proteins, aiming for the upper end of the 1.6 to 2.2 g/kg range is a reasonable strategy.
What Common Foods Actually Provide
Knowing your daily target is only useful if you can translate it into real food. Here’s what typical portions deliver:
- Chicken, beef, turkey, pork, or lamb: about 7 grams per ounce, so a 4-ounce serving gives you roughly 28 grams
- Eggs: 6 grams each, so a three-egg meal provides about 18 grams
- Greek yogurt (plain, nonfat): 12 to 18 grams per 5-ounce container
- Lentils: 9 grams per half cup cooked
For someone targeting 150 grams a day, a realistic day might look like: three eggs and Greek yogurt at breakfast (24 to 30 grams), 6 ounces of chicken at lunch (42 grams), a protein shake or lentil-based meal as a snack (20 to 25 grams), and 6 ounces of beef or fish at dinner (42 grams). That gets you to roughly 130 to 140 grams before counting the protein in grains, nuts, or other foods throughout the day.
Where the Ceiling Actually Is
There is a point where more protein simply doesn’t help you build more muscle. Per-meal, that ceiling sits around 0.3 g/kg of body weight for younger adults (roughly 20 to 25 grams from a high-quality source). Per day, the breakpoint is around 1.6 g/kg, with a confidence interval stretching up to 2.2 g/kg. Eating beyond those levels isn’t harmful for healthy people, but the extra protein gets used for energy or other metabolic processes rather than building additional muscle tissue.
If you’re young, eating at maintenance calories, and training consistently, 1.6 g/kg/day with even distribution across four meals is a solid, evidence-backed target. If you’re older, dieting, or relying on plant-based sources, push closer to 2.0 to 2.4 g/kg/day to account for the reduced efficiency at each of those steps.