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 165-pound person, that’s roughly 60 grams. But this baseline number is designed to prevent deficiency in sedentary adults, not to optimize health, and newer dietary guidelines suggest most people benefit from eating more.
The 2025-2030 Dietary Guidelines for Americans recommend a range of 1.2 to 1.6 grams per kilogram of body weight per day. For someone weighing 150 pounds, that translates to 82 to 108 grams of protein daily. Where you fall in that range depends on your age, activity level, and whether you’re pregnant or breastfeeding.
What Sedentary Adults Actually Need
If you spend most of your day sitting at a desk and don’t exercise regularly, 0.8 grams per kilogram is enough to keep your body in nitrogen balance, meaning you’re replacing the protein your cells break down each day. A 140-pound sedentary person needs about 51 grams. A 200-pound sedentary person needs about 73 grams. Most Americans already hit this number without trying.
That said, “enough to prevent deficiency” and “enough to feel your best” aren’t the same thing. The updated guidelines pushing the floor to 1.2 grams per kilogram reflect growing evidence that slightly higher protein intake supports better body composition, appetite control, and metabolic health even in people who aren’t athletes.
How Protein Needs Change With Age
Adults over 65 lose muscle mass faster than younger adults, a process called sarcopenia that accelerates with each decade. The standard 0.8-gram recommendation doesn’t account for this. Researchers now recommend that older adults consume 1.0 to 1.2 grams of protein per kilogram of body weight daily to slow muscle loss and maintain strength. For a 160-pound older adult, that means aiming for 73 to 87 grams per day rather than the baseline 58 grams.
The one exception: people with kidney disease. Higher protein intake increases the workload on your kidneys by raising acids and waste products that need to be filtered out. For anyone with compromised kidney function, sticking closer to the baseline or following a nephrologist’s guidance is important.
Requirements During Pregnancy and Breastfeeding
Protein needs rise gradually during pregnancy. In the first trimester, the increase is negligible. By the second trimester, you need roughly 9 to 10 extra grams per day above your normal intake. In the third trimester, that jumps to about 28 to 31 extra grams per day, reflecting the rapid growth happening in the final months. A practical way to think about it: protein needs climb from about 0.8 grams per kilogram early in pregnancy to roughly 1.0 gram per kilogram by the end.
During breastfeeding, the demand stays elevated. In the first six months of exclusive nursing, you need about 19 extra grams of protein per day. After six months, when most babies are also eating solid food, that drops to around 13 grams extra.
Why Higher Protein Helps With Weight Loss
Protein is the most satiating macronutrient, meaning it keeps you feeling full longer than the same number of calories from carbohydrates or fat. This effect is well documented. In one trial, people who ate 30% of their calories from protein spontaneously ate less food and lost about 11 pounds over 12 weeks, including over 8 pounds of pure fat, without being told to restrict calories at all.
A large meta-analysis of 24 controlled trials found that dieters eating 1.07 to 1.60 grams of protein per kilogram (roughly 27% to 35% of total calories) lost more weight and more fat than dieters eating standard protein levels on the same number of calories. They also retained nearly a pound more lean muscle and burned more calories at rest. That metabolic edge matters because losing muscle during a diet slows your metabolism and makes regain more likely.
Getting 25% to 30% of your daily calories from protein appears to be a practical sweet spot. For someone eating 1,800 calories a day, that’s 112 to 135 grams of protein. Studies lasting 10 to 12 weeks at this level have found no adverse effects in healthy adults.
How to Spread Protein Across Meals
Your body can only use so much protein at once for building and repairing muscle. Research shows that muscle-building peaks at about 30 grams of protein in a single meal, and eating more than that in one sitting doesn’t increase the response. A study on leg strength and lean mass found that people who regularly ate meals containing 30 to 45 grams of protein had the greatest muscle mass and strength, particularly as they aged.
This means eating 90 grams of protein at dinner and skipping it at breakfast is less effective than spreading that same amount across three meals. Aiming for 30 to 40 grams per meal, two or three times a day, gives your muscles repeated signals to rebuild throughout the day. For context, 30 grams of protein is roughly a palm-sized portion of chicken, a cup of Greek yogurt with a handful of nuts, or about four eggs.
Animal vs. Plant Protein Quality
Not all protein sources deliver amino acids to your body with equal efficiency. Animal proteins like whey, eggs, and beef score significantly higher on digestibility measures because they contain all essential amino acids in proportions your body can readily use. Whey protein, for example, scores well above the 100% threshold on every essential amino acid. Soy protein scores around 86%, which is still good but meaningfully lower. Other plant proteins like beans and grains score lower still.
This doesn’t mean plant-based diets can’t provide enough protein. It means you may need to eat a slightly higher total amount and combine different sources (grains with legumes, for instance) to cover all your amino acid needs. If you’re eating entirely plant-based and aiming for 1.2 grams per kilogram, bumping that up to 1.4 or so can compensate for the lower digestibility.
Is Too Much Protein Harmful?
There’s no established upper limit for protein in healthy adults, but that doesn’t mean more is always better. Eating large amounts of protein forces your kidneys to filter more waste products and acids. For people with healthy kidneys, this extra workload is manageable at moderate levels. But consistently extreme intakes, well above 2 grams per kilogram, may strain even healthy kidneys over time.
The practical ceiling for most people falls somewhere around 1.6 grams per kilogram for general health, or up to 2.0 grams per kilogram for serious athletes during intense training. Beyond that, you’re unlikely to see additional muscle-building benefits, and the excess protein is simply burned for energy or stored, just like any other calorie surplus.