Most adults need at least 0.8 grams of protein per kilogram of body weight per day, which works out to about 0.36 grams per pound. For a 150-pound person, that’s roughly 54 grams; for someone weighing 180 pounds, about 65 grams. But that number is a floor, not a target. It represents the minimum to prevent deficiency in a sedentary adult, and a growing body of evidence suggests many people benefit from eating well above it.
The Baseline for Sedentary Adults
The Recommended Dietary Allowance of 0.8 g/kg was set to cover the needs of 97.5% of healthy adults. If you weigh 70 kg (about 154 pounds), that translates to 56 grams of protein a day. Two chicken breasts, a cup of Greek yogurt, and a handful of almonds would get you there without much effort. For people who sit at a desk most of the day and have no specific body composition goals, this amount keeps basic cellular repair and immune function running smoothly.
That said, many nutrition researchers now view the RDA as too conservative for optimal health. It was designed to prevent deficiency, not to optimize muscle mass, satiety, or metabolic health. If you’re active, aging, losing weight, or pregnant, your needs are meaningfully higher.
How Exercise Changes the Math
Regular physical activity increases protein turnover in your muscles, meaning you break down and rebuild more tissue than a sedentary person does. Endurance athletes like distance runners are generally advised to consume 1.2 to 1.4 g/kg per day. For a 70 kg runner, that’s 84 to 98 grams daily, roughly 50 to 75% more than the baseline RDA.
Strength training pushes the requirement even higher. Most sports nutrition guidelines place the range for people doing serious resistance training at 1.6 to 2.2 g/kg per day. At the upper end, a 180-pound lifter might aim for around 180 grams daily. Research consistently shows that intakes in this range support greater gains in muscle size and strength compared to eating at or near the RDA, especially when combined with a progressive training program.
Protein for Weight Loss
When you cut calories, your body doesn’t just burn fat. It also breaks down muscle for energy, and losing muscle slows your metabolism and makes it harder to keep weight off long term. Higher protein intake during a caloric deficit helps protect lean mass. Aiming for 1.2 to 1.6 g/kg per day is a practical range for most people trying to lose fat while holding onto muscle. For a 180-pound person, that works out to roughly 98 to 130 grams a day.
Protein also has a strong effect on appetite. Gram for gram, it’s more filling than carbohydrates or fat, partly because it takes more energy to digest and partly because it triggers satiety hormones more effectively. People who increase their protein intake during a diet often report feeling less hungry between meals, which makes sticking to a calorie deficit considerably easier.
Why Older Adults Need More
After about age 50, your body becomes less efficient at turning dietary protein into muscle tissue. This phenomenon, sometimes called anabolic resistance, means older adults need a larger dose of protein to trigger the same muscle-building response that a smaller dose would produce in a 25-year-old. Without enough protein, gradual muscle loss accelerates, increasing the risk of falls, fractures, and loss of independence.
Researchers now recommend that older adults consume 1.0 to 1.6 g/kg per day. For a 180-pound man, that translates to about 82 to 130 grams daily. The current RDA doesn’t distinguish between age groups, setting the same 0.8 g/kg target for a 30-year-old and a 75-year-old, but emerging evidence strongly suggests that older adults who eat closer to 1.2 g/kg or above maintain more muscle and strength over time. The one important exception: people with existing kidney disease should work with their doctor before increasing protein, since the kidneys handle the bulk of protein’s metabolic waste.
Protein During Pregnancy and Breastfeeding
Protein needs increase progressively throughout pregnancy. In the first trimester, the additional requirement is minimal, only about 1 gram per day above normal. By the second trimester, that rises to roughly 9 extra grams. In the third trimester, the jump is significant: an additional 28 to 31 grams per day on top of your pre-pregnancy needs. For someone who normally requires about 55 grams, third-trimester intake should be closer to 85 grams daily.
During breastfeeding, the body continues to demand extra protein to produce milk. Exclusively breastfeeding mothers need roughly 19 additional grams per day for the first six months. After six months, when babies start eating solid food and nursing less, the extra requirement drops to about 13 grams per day.
Spreading Protein Across Meals
Your body can only use so much protein for muscle building in one sitting. Research on younger adults suggests that muscle protein synthesis peaks at roughly 20 to 25 grams of high-quality protein per meal. Eating 60 grams at dinner and 10 grams at breakfast is less effective for muscle maintenance than distributing protein more evenly.
A practical framework: aim for about 0.4 g/kg per meal across at least four eating occasions. For someone targeting 1.6 g/kg per day, that’s roughly 28 grams per meal for a 70 kg person. If you’re aiming for the higher end of 2.2 g/kg per day, you’d need about 0.55 g/kg per meal, or around 38 grams per sitting for that same person. This doesn’t need to be precise at every meal, but the general principle of avoiding lopsided distribution holds up well in the research.
Older adults may actually need a slightly higher per-meal threshold, closer to 30 to 40 grams, to overcome anabolic resistance and trigger a meaningful muscle-building response.
Is Too Much Protein Harmful?
For healthy people with normal kidney function, there’s no strong evidence that high protein intake causes kidney damage. Some studies have found that eating more protein increases your kidneys’ filtration rate, but this appears to be an adaptive response rather than a sign of harm. In healthy overweight adults, increasing protein from about 91 to 108 grams per day raised filtration rate and kidney volume without negative effects.
That said, routinely eating above 2.0 g/kg per day may carry risks. Some research has linked very high protein intakes to increased rates of chronic disease and higher mortality, though the quality of protein sources (processed meat versus fish and legumes, for example) likely plays a role in those associations. For most people, staying between 1.2 and 2.0 g/kg per day covers the range between adequate and optimal without venturing into potentially excessive territory.
Quick Reference by Body Weight
- 130 pounds (59 kg): baseline 47 g, active 71 to 95 g, older adult 59 to 95 g
- 150 pounds (68 kg): baseline 54 g, active 82 to 109 g, older adult 68 to 109 g
- 180 pounds (82 kg): baseline 66 g, active 98 to 131 g, older adult 82 to 131 g
- 200 pounds (91 kg): baseline 73 g, active 109 to 145 g, older adult 91 to 145 g
These ranges use 0.8 g/kg for baseline, 1.2 to 1.6 g/kg for active individuals, and 1.0 to 1.6 g/kg for older adults. If you’re strength training seriously, you can push toward 2.0 g/kg. The “right” number depends on your goals, your age, and how active you are, but for most people who exercise regularly, landing somewhere between 1.2 and 1.6 g/kg is a well-supported target.