Most healthy adults need at least 0.8 grams of protein per kilogram of body weight per day, which works out to roughly 50 to 75 grams for someone eating around 2,000 calories. That baseline keeps you from deficiency, but it’s not necessarily the amount that keeps you feeling strong, full, or recovering well. Your actual target depends on your activity level, age, and goals.
The Baseline for Healthy Adults
The Recommended Dietary Allowance of 0.8 g/kg per day has been essentially unchanged for over 70 years. For a 150-pound (68 kg) person, that’s about 54 grams of protein. For a 200-pound (91 kg) person, it’s roughly 73 grams. The World Health Organization puts it at 10 to 15 percent of total daily calories, which lines up with those same numbers on a standard diet.
This number represents the minimum to avoid deficiency in nearly all healthy people. It’s not a target for optimal health, athletic performance, or preserving muscle as you age. Think of it as the floor, not the ceiling.
How Exercise Changes Your Needs
If you lift weights regularly and want to build or maintain muscle, the evidence points to 1.6 g/kg per day as the sweet spot. A large meta-analysis found that protein intake beyond 1.6 g/kg per day didn’t produce additional muscle growth from resistance training, though intakes up to 2.2 g/kg per day are common and considered safe. For a 170-pound person, that range is roughly 123 to 170 grams per day.
Endurance athletes have their own requirements. Runners, cyclists, and swimmers typically consume around 1.5 g/kg per day, but newer research using more precise measurement methods suggests they actually need closer to 1.8 g/kg per day. During periods of hard training, restricted carbohydrate intake, or low overall calories, that number climbs to about 2.0 g/kg per day.
Protein for Weight Loss
Higher protein diets consistently help people lose more fat and keep more muscle during a calorie deficit. In clinical trials, the groups that did best typically ate between 1.07 and 1.60 g/kg per day, or roughly 25 to 35 percent of their total calories from protein. On a 1,600-calorie diet, 30 percent protein translates to about 120 grams.
Protein’s advantage during weight loss is partly mechanical: it’s the most filling macronutrient. One study found that when participants switched to a diet with 30 percent protein (keeping calories the same), they spontaneously ate about 441 fewer calories per day once they were allowed to eat freely. That kind of appetite reduction makes sticking to a calorie deficit dramatically easier.
Why Older Adults Need More
The standard 0.8 g/kg recommendation has drawn criticism from researchers who study age-related muscle loss (sarcopenia). As you get older, your muscles become less responsive to protein. The same 20-gram serving that triggers a strong muscle-building response in a 25-year-old produces a weaker one in a 65-year-old. To compensate, older adults need more protein per meal, roughly 25 to 30 grams of high-quality protein at each sitting. Some older men may need as much as 0.60 g/kg per meal to get the same response younger adults get from 0.40 g/kg.
For daily totals, many experts working in this area recommend that adults over 65 aim well above the RDA. Hitting 1.2 to 1.6 g/kg per day, spread across multiple meals, is a practical target for maintaining strength and independence with age.
Protein Needs During Pregnancy and Breastfeeding
Protein requirements increase progressively through pregnancy. In the first trimester, the increase is negligible, just an extra gram or so per day. By the second trimester, you need an additional 9 to 10 grams daily. In the third trimester, the jump is significant: 28 to 31 extra grams per day on top of your normal intake. For a woman who would otherwise need about 48 grams, that means roughly 75 to 80 grams daily by late pregnancy.
During breastfeeding, the extra requirement is about 19 to 23 grams per day for the first six months, dropping to around 13 grams once you start introducing solid foods and nursing less frequently.
How to Spread Protein Across Meals
Your body can use more protein in one sitting than the old “30 grams per meal” myth suggests, but distribution still matters. The current evidence recommends roughly 0.4 g/kg per meal across at least four eating occasions to maximize muscle building. For a 175-pound person, that’s about 32 grams per meal. If you’re aiming for the higher end of the range (2.2 g/kg per day), you’d need about 0.55 g/kg per meal, or around 44 grams four times daily.
The practical takeaway: don’t load all your protein into dinner. A common pattern, especially in Western diets, is a low-protein breakfast (toast, cereal), a moderate lunch, and a protein-heavy dinner. Redistributing that intake more evenly gives your muscles more opportunities to repair and grow throughout the day. This is especially important for older adults, who benefit most from consistent protein at every meal.
Not All Protein Sources Are Equal
Protein quality depends on two things: the amino acid profile (whether it contains all the building blocks your muscles need) and how well your body can actually digest and absorb those amino acids.
Animal proteins, including meat, dairy, and eggs, score highest on digestibility, with essential amino acid absorption rates of 90 percent or above. Whey protein isolate scores between 94 and 100 percent on the most current quality scale (DIAAS). Beef ranges from 80 to 121 percent depending on preparation and cut. Soy protein isolate also scores at or above 100 percent, making it one of the strongest plant options.
Whole legumes, grains, and vegetables have good digestibility (80 percent or higher), but individual plant proteins are often low in one or two essential amino acids. Pea protein, for example, scores anywhere from 61 to 100 percent depending on whether you’re eating whole green peas or a processed protein isolate. Nuts and seeds have the lowest average digestibility at around 71 percent. If you eat a plant-based diet, combining different protein sources throughout the day (grains plus legumes, for instance) covers the gaps reliably. You don’t need to combine them at every meal.
Is Too Much Protein Harmful?
For people with healthy kidneys, intakes up to 1.6 g/kg per day are well-supported and show no evidence of harm. Research has found that protein up to 1.66 g/kg per day does not pose a health hazard in otherwise healthy people on calorie-restricted diets.
The concern with very high protein intake centers on kidney function. High dietary protein increases blood flow and pressure inside the kidneys, a process called hyperfiltration. In the short term, this shows up as elevated filtration rates, and it’s a normal physiological response (the same thing happens during pregnancy without causing damage). The question is whether sustained hyperfiltration over years can wear on the kidneys. For people who already have chronic kidney disease or risk factors for it, high protein diets can accelerate kidney damage. For healthy individuals, the evidence doesn’t show clear harm, but long-term data at intakes above 2.0 g/kg per day is limited.
If you have diabetes, high blood pressure, or a family history of kidney disease, it’s worth getting your kidney function checked before committing to a very high protein diet. For most healthy adults eating between 1.2 and 2.0 g/kg per day, the benefits for muscle, satiety, and body composition outweigh the theoretical risks.
Quick Reference by Body Weight
- 130 lbs (59 kg): Minimum 47 g, active 94–130 g, weight loss 63–94 g
- 150 lbs (68 kg): Minimum 54 g, active 109–150 g, weight loss 73–109 g
- 175 lbs (80 kg): Minimum 64 g, active 128–176 g, weight loss 86–128 g
- 200 lbs (91 kg): Minimum 73 g, active 146–200 g, weight loss 97–146 g
- 225 lbs (102 kg): Minimum 82 g, active 163–224 g, weight loss 109–163 g
The “minimum” column uses 0.8 g/kg, “active” uses 1.6 to 2.2 g/kg for strength training, and “weight loss” uses 1.07 to 1.6 g/kg. If you’re overweight, basing calculations on your goal weight or lean body mass gives a more accurate target than using your current weight.