Most adults need at least 0.36 grams of protein per pound of body weight per day, which works out to about 54 grams for a 150-pound person. But that baseline number is a minimum to prevent deficiency, not necessarily the amount that’s optimal for your body and goals. Your actual needs depend on your age, activity level, whether you’re pregnant, and whether you’re trying to lose weight or build muscle.
The Baseline: What Most Adults Need
The Recommended Dietary Allowance for protein is 0.8 grams per kilogram of body weight, or 0.36 grams per pound. For a 150-pound person, that’s roughly 54 grams per day. For a 200-pound person, it’s about 72 grams. The World Health Organization frames it slightly differently, suggesting protein make up 10 to 15 percent of total daily calories, which lands around 50 to 75 grams for someone eating 2,000 calories a day.
These numbers assume you’re a generally healthy adult with a moderate activity level. They’re designed to meet the needs of most people, but they don’t account for situations where your body is under extra demand, like intense exercise, aging, pregnancy, or calorie restriction.
How to Calculate Your Number
Start by converting your weight to kilograms (divide your weight in pounds by 2.2). Then multiply by the factor that matches your situation:
- Sedentary adult: 0.8 g per kg (the RDA baseline)
- Weight loss while preserving muscle: 1.0 to 1.2 g per kg
- Building muscle or regular strength training: 1.0 to 1.5 g per kg
- Adults over 65: 1.0 to 1.2 g per kg
- Pregnancy (third trimester): baseline plus 28 to 31 extra grams per day
- Breastfeeding: baseline plus 19 to 23 extra grams per day
So a 170-pound person (about 77 kg) who strength trains three times a week would aim for 77 to 116 grams of protein daily. That same person, if sedentary, would need only about 62 grams.
Why You Need More During Weight Loss
When you eat fewer calories than your body burns, you lose both fat and muscle. Protein is what protects your muscle tissue during that process. Bumping your intake to 1.0 to 1.2 grams per kilogram helps your body preferentially burn fat while holding onto lean mass. For a 150-pound person in a calorie deficit, that translates to roughly 68 to 82 grams per day.
Protein also keeps you fuller longer than carbohydrates or fat do, which makes sticking to a calorie deficit more manageable. If you’ve ever noticed that a breakfast of eggs holds you over until lunch while toast leaves you hungry by 10 a.m., that’s the satiety effect of protein at work.
Why You Need More as You Age
Adults start losing muscle mass gradually after age 30, and the rate accelerates after 65. This age-related muscle loss, called sarcopenia, contributes to falls, fractures, and loss of independence. Older adults don’t use protein as efficiently as younger people do, so they need more of it to maintain the same amount of muscle. Most experts recommend older adults aim for at least 1.0 to 1.2 grams per kilogram, meaningfully above the standard RDA.
Protein Needs During Pregnancy and Breastfeeding
Protein requirements climb during pregnancy, but not evenly across all nine months. In the first trimester, the increase is negligible, just an extra gram or two per day. By the second trimester, you need an additional 6 to 9 grams daily. The third trimester is where demand peaks, with recommendations calling for 17 to 31 extra grams per day on top of your normal intake, depending on which set of guidelines you follow.
During breastfeeding, the extra demand stays elevated at roughly 19 to 23 additional grams per day for the first six months, then drops slightly to 12 to 13 extra grams once you begin introducing solid foods to your baby.
How Much per Meal Matters
Your body can only use so much protein at once for muscle repair. The practical ceiling appears to be around 30 grams of high-quality protein per meal. That’s the amount needed to trigger the muscle-building process effectively. Eating more than 40 grams in a single sitting doesn’t appear to provide additional benefit for muscle repair or growth.
Distribution throughout the day matters more than most people realize. One study found that spreading protein evenly across breakfast, lunch, and dinner boosted muscle building by about 25 percent compared to the common pattern of eating very little protein at breakfast and loading up at dinner. If your daily target is 90 grams, aim for roughly 30 grams at each meal rather than 10 at breakfast, 20 at lunch, and 60 at dinner.
Plant Protein vs. Animal Protein
Not all protein is created equal when it comes to how well your body absorbs and uses it. Dairy proteins consistently score at the top for digestibility and amino acid quality. Soy protein and soy flour rank as “good” quality sources. Pea protein concentrate and wheat protein fall lower on the scale, meaning your body extracts less usable protein from them gram for gram.
This doesn’t mean plant-based diets can’t meet your protein needs. It does mean that if most of your protein comes from plants, especially grains and legumes rather than soy, you may need to eat a somewhat higher total amount to get the same effective dose. Combining different plant sources throughout the day (beans with rice, lentils with nuts) helps cover a wider range of amino acids. If you rely heavily on wheat-based protein sources like seitan, be aware that wheat scores particularly low for digestibility.
When Protein Becomes Too Much
For most healthy adults, the practical upper limit is about 2 grams per kilogram of ideal body weight per day. For a 140-pound person, that’s roughly 125 grams. Going above about 0.9 grams per pound (around 150 grams daily for a 165-pound person) can start to cause problems.
Very high protein diets increase the risk of kidney stones. If you already have reduced kidney function, excess protein forces your kidneys to work harder to filter waste products, which can accelerate damage. People with existing kidney disease need to be especially careful about protein intake. For everyone else, staying under that 2 g/kg ceiling provides a generous range to work within for virtually any fitness or health goal.
Putting It All Together
The simplest approach is to multiply your weight in kilograms by the factor that fits your life right now. If you’re a 160-pound person (73 kg) who exercises regularly and wants to maintain muscle, multiplying by 1.2 gives you about 87 grams per day. Split that across three meals at roughly 29 grams each, and you’re covering both your daily total and the per-meal threshold that maximizes muscle repair.
Track your intake for a few days using a food app or nutrition label to see where you currently land. Many people discover they’re already hitting their target at lunch and dinner but falling short at breakfast. Adding a protein source to your morning meal, whether that’s eggs, Greek yogurt, or a protein-rich smoothie, is often the easiest adjustment to make.