Most women need between 46 and 65 grams of protein per day, but the right number for you depends on your 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 0.36 grams per pound. For a sedentary 140-pound woman, that’s roughly 53 grams daily. But that baseline is a minimum to prevent deficiency, not necessarily an optimal target.
Calculating Your Baseline
The simplest way to find your starting number: multiply your weight in pounds by 0.36. A 130-pound woman lands at about 47 grams per day. A 160-pound woman needs around 58 grams. These figures assume you’re relatively sedentary and not pregnant, breastfeeding, or recovering from illness or surgery.
That said, many nutrition researchers now consider 0.8 g/kg a floor rather than a goal. If you’re trying to maintain muscle, lose weight, or stay active, your needs are almost certainly higher.
How Activity Level Changes the Number
Women who exercise regularly, whether through running, cycling, weight training, or group fitness, benefit from significantly more protein than the baseline. Research supports long-term intake of up to 2 grams per kilogram of body weight (about 0.9 g per pound) as safe for healthy adults. For a 150-pound woman, that range spans from roughly 55 grams at the low end to 136 grams at the higher end, depending on training intensity.
A practical middle ground for moderately active women is 1.2 to 1.6 grams per kilogram, or about 0.5 to 0.7 grams per pound. That puts most women somewhere between 70 and 110 grams per day. If you strength train several times per week and want to build or maintain muscle, aim toward the higher end of that range.
Protein Needs During Pregnancy and Breastfeeding
Pregnancy increases protein requirements to about 60 grams per day, up from the standard 46 grams recommended for non-pregnant women. Your body uses that extra protein to support the placenta, expand blood volume, and build fetal tissue. Most of the increased demand kicks in during the second and third trimesters.
Breastfeeding raises the bar even further. Current guidelines call for an additional 25 grams per day on top of your normal needs, which brings most nursing women to roughly 71 grams daily. Since appetite often increases during lactation, hitting this target through whole foods is usually manageable without supplementation.
Why Women Over 50 Need More
Nearly half of all protein in your body is found in muscle tissue, and muscle mass naturally declines with age. This gradual loss, called sarcopenia, accelerates after menopause when estrogen levels drop. The standard recommendation of 0.8 g/kg doesn’t account for this shift, which is why many researchers now suggest older adults aim for 1.0 to 1.2 grams per kilogram per day.
For a 150-pound woman over 60, that translates to roughly 68 to 82 grams of protein daily. Spreading that intake across meals matters more as you age, because the body becomes less efficient at using protein in large single doses. Three to four meals each containing 20 to 30 grams is more effective for maintaining muscle than eating most of your protein at dinner.
Protein for Weight Loss
If you’re eating in a calorie deficit, protein becomes even more important. A 12-week study of women ages 28 to 80 compared two diets with the same calorie reduction: one with 18% of calories from protein and one with 30%. Both groups lost weight, but the higher-protein group lost nearly half as much muscle (1.5 kg versus 2.8 kg). The higher-protein group also reported feeling more satisfied and finding the diet more pleasant to follow.
Aiming for about 30% of your total calories from protein is a reasonable target during weight loss. On a 1,500-calorie diet, that works out to roughly 112 grams. On a 1,200-calorie diet, about 90 grams. This helps you hold onto muscle while losing fat, which keeps your metabolism from slowing as much during a deficit.
How to Spread Protein Across Meals
Your body can use protein more effectively when it’s distributed throughout the day rather than concentrated in one or two meals. Research suggests that 20 to 25 grams of high-quality protein per meal is enough to trigger the muscle-building response in younger adults. Older adults may need slightly more per sitting.
A practical framework: aim for 0.4 grams per kilogram of body weight at each of four meals. For a 140-pound woman targeting 1.6 g/kg daily, that’s about 25 grams per meal across four eating occasions. If you eat three meals a day, you’d want roughly 33 grams each. The key is avoiding the common pattern of a low-protein breakfast (a piece of toast, a banana), a modest lunch, and then trying to catch up at dinner.
Common Foods and Their Protein Content
Knowing the numbers is only useful if you can translate them to your plate. Here’s what protein looks like in real portions:
- 4 oz chicken breast (raw): about 22 grams
- Two large eggs: about 12 grams
- 1 cup plain low-fat yogurt: about 12 grams (Greek yogurt typically has 15 to 20 grams)
- 1 scoop soy protein powder: about 25 grams
- 1 cup cooked lentils: about 18 grams
- 4 oz salmon: about 23 grams
A breakfast of two eggs with a cup of Greek yogurt gets you to roughly 30 grams before lunch. A palm-sized portion of chicken or fish at lunch and dinner adds another 40 to 50 grams easily. Snacks like cottage cheese, edamame, or a handful of almonds fill in the gaps.
Upper Limits and Safety
Long-term intake of up to 2 grams per kilogram of body weight per day is considered safe for healthy adults. For a 140-pound woman, that’s about 127 grams. The tolerable upper limit in research is 3.5 g/kg per day, but that’s only documented as safe in people who have gradually adapted to very high intakes, like competitive athletes.
Chronically exceeding 2 g/kg per day without a specific athletic reason can strain digestion and, over time, place extra demands on the kidneys. If you have existing kidney disease, protein recommendations are different and should be individualized. For most healthy women, staying between 1.0 and 2.0 g/kg covers everything from general health to serious training goals.