Your daily protein target depends on your body weight, activity level, age, and goals. The baseline recommendation for healthy adults is 0.8 grams per kilogram of body weight (about 0.36 grams per pound), but that number represents the bare minimum to avoid deficiency, not the amount that supports optimal health. Most people benefit from significantly more. A quick way to estimate your needs: multiply your weight in kilograms by a factor between 1.2 and 2.2, depending on your situation.
How to Calculate Your Protein Needs
Protein recommendations are based on body weight, not calorie intake. The formula is simple: take your weight in kilograms (divide pounds by 2.2) and multiply by the grams-per-kilogram target that fits your life. Here are the ranges backed by current nutrition guidelines:
- Generally healthy, lightly active adults: at least 1.2 g/kg per day
- Fat loss while preserving muscle: 1.2–1.6 g/kg per day
- Fat loss while maximizing muscle gain: 1.6–2.4 g/kg per day
- Muscle building with adequate calories: 1.6–2.2 g/kg per day
- Endurance and strength athletes: 1.2–2.0 g/kg per day (up to 2.4–2.7 g/kg during calorie restriction)
- Adults over 65: at least 1.2 g/kg per day
- Pregnant or breastfeeding women: at least 1.7 g/kg per day
So a 70 kg (154 lb) person focused on muscle growth would aim for 112 to 154 grams of protein per day. That same person, if sedentary and just trying to stay healthy, would need a minimum of 84 grams. A 60 kg (132 lb) woman trying to lose fat while keeping muscle would target 72 to 96 grams daily.
Why the RDA Is Too Low for Most People
The Recommended Dietary Allowance of 0.8 g/kg was designed to prevent protein deficiency in the general population. Harvard Health has described it as “the minimum amount you need to keep from getting sick,” not a target for thriving. For a 70 kg adult, that’s only 56 grams per day, a number that falls well short of what research supports for maintaining muscle, supporting recovery, or losing weight effectively.
A 2018 meta-analysis found that protein intake averaging 1.6 g/kg per day maximized muscle gains from resistance training, with the upper confidence interval reaching 2.2 g/kg. This is why major sports nutrition organizations, including the American College of Sports Medicine and the International Society of Sports Nutrition, recommend 1.2 to 2.0 g/kg for active individuals. Even sedentary people appear to benefit from intakes above the RDA.
Adjustments for Age
Muscle mass declines naturally with aging, a process called sarcopenia. Nearly half of all protein in your body is stored in muscle, so losing it has real consequences for strength, balance, and independence. The official RDA for older adults is the same 0.8 g/kg as younger adults, but researchers who study aging now recommend 1.0 to 1.2 g/kg as a baseline for healthy adults over 65. Older adults who are recovering from illness, surgery, or a period of inactivity should aim for at least 1.6 g/kg.
Older adults also need more protein per meal to get the same muscle-building response. Younger adults can stimulate muscle repair with about 0.24 g/kg per meal, while older adults need roughly 0.40 g/kg per meal to achieve the same effect. In practical terms, that means a 75 kg older adult should aim for about 30 grams of protein at each meal rather than clustering it at dinner.
Protein Needs During Pregnancy
Protein requirements increase throughout pregnancy, rising most sharply in the third trimester. European and international guidelines agree on the pattern: protein needs barely change in the first trimester (just 1 gram extra per day), rise by about 9 grams per day in the second trimester, and jump by 28 to 31 grams per day in the third trimester. During breastfeeding, the recommendation is roughly 19 to 23 extra grams per day in the first six months, tapering slightly after that.
Some researchers simplify this to a single target: at least 1.7 g/kg per day for pregnant and lactating women. For a 65 kg woman, that translates to about 110 grams daily.
Does Protein Source Matter?
Animal proteins have traditionally been considered superior for muscle building because they contain higher concentrations of leucine, the amino acid that triggers muscle repair. Each meal needs roughly 2.5 to 3 grams of leucine to fully activate that process, which translates to about 30 to 35 grams of high-quality animal protein per sitting.
Plant proteins tend to be lower in leucine gram for gram, which is why some guidelines suggest plant-based eaters may need a higher total protein intake. However, recent research from the American Society for Nutrition found that high-protein vegan and omnivorous diets produced comparable rates of muscle growth and muscle protein synthesis in young adults. The key finding: when total protein intake is high enough, the source matters less. Animal protein isn’t required for muscle growth if you’re consistently hitting your overall daily target through a variety of plant sources.
How to Spread Protein Across the Day
Your body can only use so much protein for muscle repair in a single sitting. Eating 100 grams at dinner and 10 grams at breakfast is less effective than distributing your intake evenly. Research on meal-level protein doses suggests young adults should aim for about 0.40 g/kg per meal to maximize the muscle-building response, while older adults benefit from 0.60 g/kg per meal.
For a 80 kg person targeting 130 grams daily, that works out to roughly 32 to 43 grams at each of three meals, with any remainder coming from snacks. Clinical studies consistently recommend at least 30 grams of high-quality protein at breakfast, a meal where most people fall short. Once muscle repair is activated by a sufficient dose of leucine, it stays elevated for about 2.5 hours before your muscles become responsive to the next feeding.
Is Too Much Protein Harmful?
The most common concern is kidney damage. Research following women over time found no association between high protein intake and declining kidney function in those with healthy kidneys. The risk appears to be limited to people who already have reduced kidney function, where high protein intake can accelerate the decline. If you have existing kidney disease, protein intake is one of the things your doctor will want to manage carefully.
For healthy adults, intakes up to 2.2 g/kg per day are well-supported by research, and athletes regularly consume 2.4 to 2.7 g/kg during cutting phases without adverse effects in studies. There’s no established toxic upper limit for protein in healthy individuals, but there’s also no evidence that going far beyond 2.2 g/kg provides additional muscle-building benefits for most people.