Most women need between 46 and 75 grams of protein per day, but the right number depends on your body weight, activity level, and life stage. The baseline recommendation is 0.8 grams of protein per kilogram of body weight, which works out to about 53 grams for a sedentary 140-pound woman. That number can nearly double if you’re very active, pregnant, or over 50.
The Baseline: 0.8 Grams per Kilogram
The standard Recommended Dietary Allowance for protein is 0.8 grams per kilogram of body weight, or about 0.36 grams per pound. For most adults, this is the minimum needed to meet basic nutritional requirements and prevent deficiency. The World Health Organization frames it slightly differently: protein should make up 10 to 15 percent of your total daily calories, which translates to roughly 50 to 75 grams on a 2,000-calorie diet.
Here’s what the baseline looks like at different body weights:
- 120 pounds (54 kg): about 44 grams per day
- 140 pounds (64 kg): about 51 grams per day
- 160 pounds (73 kg): about 58 grams per day
- 180 pounds (82 kg): about 65 grams per day
These numbers assume you’re relatively sedentary and not in a life stage that increases your needs. For many women, the baseline is a floor, not a target.
How Exercise Changes the Number
If you work out regularly, your protein needs climb. Women who exercise consistently, whether that’s running, cycling, swimming, or group fitness classes, do best with about 1.1 to 1.5 grams per kilogram of body weight. If you lift weights or train seriously for endurance events, that range shifts to 1.2 to 1.7 grams per kilogram.
For a 150-pound woman who strength trains three or four times a week, that means roughly 82 to 116 grams of protein daily. That’s a significant jump from the 54-gram baseline, and it reflects the extra protein your muscles need to repair and grow after training. Eating closer to the lower end of the range is fine for moderate activity. Push toward the higher end if you’re training hard, building muscle, or recovering from intense sessions.
Protein Needs After Menopause
Women over 50 lose muscle mass faster than younger women, a process that accelerates after menopause when estrogen levels drop. Muscle loss increases the risk of falls, fractures, and metabolic slowdown. To counteract this, experts at Mayo Clinic recommend women after menopause aim for 1.0 to 1.2 grams of protein per kilogram of body weight daily, well above the standard 0.8-gram baseline.
For a 150-pound postmenopausal woman, that’s 68 to 82 grams per day. The higher end of that range is particularly relevant if you exercise regularly, are losing weight, or are older than 65. Pairing higher protein intake with resistance exercise is the most effective strategy for preserving muscle and bone density through this transition.
Pregnancy and Breastfeeding
Protein needs during pregnancy increase gradually, not all at once. In the first trimester, you barely need any extra protein beyond your normal intake, just an additional gram or so per day. By the second trimester, you need roughly 9 to 10 additional grams daily. In the third trimester, that jumps to about 28 to 31 extra grams per day, as the baby’s growth accelerates rapidly.
For a woman who normally needs about 50 grams of protein, third-trimester needs could reach 78 to 81 grams daily. Some guidelines describe this as gradually increasing from 0.8 grams per kilogram early in pregnancy to about 1.0 gram per kilogram by the end.
During breastfeeding, protein needs stay elevated. In the first six months of exclusive breastfeeding, you need roughly 19 extra grams of protein per day. After six months, when your baby starts eating solid foods and nursing less, that drops to about 13 grams extra. This puts most breastfeeding women around 1.1 to 1.2 grams per kilogram daily.
Protein for Weight Loss
If you’re trying to lose weight, protein becomes even more important. Higher protein intake helps preserve lean muscle during a calorie deficit, keeps you feeling full longer, and slightly boosts the number of calories your body burns at rest. A meta-analysis of 24 trials found that people eating 1.07 to 1.60 grams of protein per kilogram per day while cutting calories lost more fat, retained more muscle, and had lower triglyceride levels than those eating standard amounts of protein.
In practical terms, getting 25 to 30 percent of your daily calories from protein is a useful target during weight loss. On a 1,500-calorie diet, that’s roughly 94 to 112 grams. One six-month trial found that participants eating protein at 25 percent of total calories lost an additional 3.7 kilograms (about 8 pounds) of body weight compared to a higher-carbohydrate group. Another study found that when people ate 30 percent of their calories from protein without restricting portions, they naturally ate less and lost about 11 pounds over 12 weeks, largely from body fat.
Research suggests that up to 1.66 grams per kilogram per day poses no health hazard for people without kidney disease.
How to Spread Protein Across the Day
Your body can only use so much protein at once for building and repairing muscle. Research suggests that 20 to 25 grams of protein per meal is the threshold that triggers the strongest muscle-building response. Eating 40 grams in one sitting and skipping protein at the next meal is less effective than distributing it evenly.
A good rule of thumb is to aim for 0.4 to 0.55 grams of protein per kilogram of body weight at each of four meals or eating occasions throughout the day. For a 140-pound woman, that works out to about 25 to 35 grams per meal. This doesn’t need to be exact. The point is to avoid the common pattern of eating almost no protein at breakfast, a modest amount at lunch, and a large amount at dinner. Even shifting some of your dinner protein to breakfast can make a meaningful difference.
To put 25 grams of protein in perspective: that’s roughly a palm-sized portion of chicken or fish, a cup of Greek yogurt, three eggs, or a cup of cooked lentils.
Is Too Much Protein Harmful?
For healthy women, high-protein diets are not known to cause medical problems. The concern about protein damaging kidneys applies specifically to people who already have kidney disease, because compromised kidneys struggle to clear the waste products of protein metabolism. If you have kidney disease, diabetes, or other chronic conditions, adjusting your protein intake is worth discussing with your doctor. For everyone else, the evidence consistently shows that protein intakes well above the 0.8-gram baseline are safe and, in many cases, beneficial.