Most adults need at least 0.36 grams of protein per pound of body weight per day, which works out to about 55 grams for a 150-pound person. That number is the bare minimum to prevent deficiency, though. Depending on your age, activity level, and goals, you likely need more.
The Baseline for Average Adults
The official Recommended Dietary Allowance (RDA) is 0.8 grams of protein per kilogram of body weight, or 0.36 grams per pound. For a 150-pound person, that’s roughly 54 grams per day. For someone at 200 pounds, it’s about 72 grams. This amount prevents muscle wasting in a sedentary adult, but it wasn’t designed to be optimal for health, fitness, or aging well.
As a percentage of total calories, adults 19 and older are advised to get 10 to 35 percent of their daily calories from protein. On a 2,000-calorie diet, that’s anywhere from 50 to 175 grams. The wide range reflects how much individual needs vary.
How Activity Level Changes the Target
If you regularly lift weights or train for endurance sports like running or cycling, your protein needs jump to 1.2 to 1.7 grams per kilogram of body weight. For a 170-pound person, that translates to roughly 93 to 131 grams per day. The higher end of that range applies if you’re doing intense strength training or trying to build muscle, while the lower end covers moderate endurance exercise.
People in a caloric deficit, meaning they’re eating less than they burn to lose weight, also benefit from higher protein intake. Research in Advances in Nutrition confirms that high protein intake helps preserve lean body mass and muscle during weight loss. Without enough protein while cutting calories, you lose muscle along with fat, which slows your metabolism and makes the weight harder to keep off. Aiming for the 1.2 to 1.6 grams per kilogram range during a diet gives your body the raw materials to hold onto muscle even as overall calories drop.
Why Older Adults Need More
After about age 65, your body becomes less efficient at using protein to maintain muscle. This gradual loss of muscle mass, called sarcopenia, accelerates with low protein intake and inactivity. Research compiled by the Administration for Community Living recommends that older adults consume 1.0 to 1.2 grams of protein per kilogram of body weight, a meaningful step up from the standard RDA.
For a 160-pound older adult, that means roughly 73 to 87 grams of protein daily instead of the 58 grams the standard RDA would suggest. Studies on elderly women show that eating at or below the RDA results in loss of body cell mass, reduced muscle function, and a weaker immune response over time. Bumping protein intake up by even 15 to 20 grams a day can make a real difference in maintaining independence and physical function.
Protein During Pregnancy and Breastfeeding
Protein needs rise steadily during pregnancy. In the first trimester, the increase is negligible (about 1 gram extra per day). By the second trimester, the recommendation climbs by roughly 9 grams per day above your normal intake, and in the third trimester it jumps to about 28 to 31 additional grams per day. For a woman who normally needs around 50 grams, that means eating closer to 80 grams daily by the end of pregnancy.
During breastfeeding, protein needs stay elevated. The first six months of exclusive breastfeeding call for about 19 extra grams per day, tapering to around 13 grams extra once the baby starts eating solid foods. That works out to roughly 1.2 grams per kilogram of body weight for lactating women.
Spreading Protein Across Meals
Your body doesn’t just care about total daily protein. How you distribute it across meals matters too. Muscle repair and growth ramp up once a meal delivers about 30 grams of high-quality protein, which provides roughly 3 grams of leucine, the amino acid that triggers the building process. Below that threshold, your body stays in a breakdown state rather than a repair state.
A 2014 study found that muscle protein synthesis was about 25 percent greater when protein was spread evenly across breakfast, lunch, and dinner compared to the typical pattern of eating very little protein at breakfast and loading up at dinner. If your daily target is 90 grams, three meals of 30 grams will do more for your muscles than eating 10 grams at breakfast, 20 at lunch, and 60 at dinner.
You may have heard that your body can only absorb 25 grams of protein at a time. That applies mainly to fast-digesting protein supplements like whey shakes. When you eat whole foods like meat, eggs, beans, or dairy, digestion is slower and your body continues absorbing and using protein well beyond that 25-gram mark. So a 40-gram chicken breast at dinner isn’t going to waste.
How Much Is Too Much
For healthy adults who aren’t elite athletes or bodybuilders, Harvard Health recommends capping protein at about 2 grams per kilogram of body weight. For a 140-pound person, that ceiling is roughly 125 grams per day. Most people eating a normal diet won’t come close to exceeding this, but it’s relevant if you’re stacking protein shakes on top of high-protein meals.
Very high protein diets carry a few specific risks. People who eat large amounts of protein have higher rates of kidney stones. And when that protein comes primarily from red and processed meat, it’s associated with increased risk of heart disease and colon cancer. The protein itself isn’t necessarily the problem in that case. It’s the saturated fat and other compounds that come packaged with it. Mixing your protein sources across poultry, fish, legumes, dairy, and eggs sidesteps most of these concerns.
If you have existing kidney disease, high protein intake can accelerate the decline in kidney function. But for people with healthy kidneys, moderate increases above the RDA are well-supported by evidence and carry minimal risk.
Quick Reference by Body Weight
- 130 lbs (59 kg): RDA minimum 47 g, active range 71–100 g, older adult range 59–71 g
- 150 lbs (68 kg): RDA minimum 54 g, active range 82–116 g, older adult range 68–82 g
- 180 lbs (82 kg): RDA minimum 65 g, active range 98–139 g, older adult range 82–98 g
- 200 lbs (91 kg): RDA minimum 73 g, active range 109–155 g, older adult range 91–109 g
These ranges use 0.8 g/kg for the RDA, 1.2 to 1.7 g/kg for active individuals, and 1.0 to 1.2 g/kg for adults over 65. Your best target depends on which category fits your life right now.