How much protein do women need?
The same grams-per-kilogram figures apply to women as to men — the research just tested far fewer of them, and a lot of surrounding advice was shaped by assumptions rather than data.
The short answer
The same numbers, per kilogram of body weight:
- Sedentary: 0.8–1.0 g/kg.
- Training regularly: 1.4–2.0 g/kg.
- Dieting while trying to keep muscle: 1.6–2.4 g/kg.
- Postmenopausal: 1.2–1.6 g/kg, higher if you train.
For a 65 kg woman training three times a week, that's roughly 90–130 g a day. The gram totals come out lower than a man's mainly because the body they're calculated from is smaller — the multiplier itself isn't sex-specific.
Why there isn't a separate set of numbers
Protein requirements scale with lean mass and with what you're asking your body to repair. Neither of those is a function of sex as such. Women do carry a higher proportion of body fat on average and less lean mass at a given body weight, but calculating from body weight already accounts for most of that.
There's a real caveat, and it's about the evidence rather than the biology: sports-nutrition research has historically studied men. An analysis of the field found women made up a minority of participants across sports and exercise science studies, and protein research specifically has leaned heavily on young trained men. So the confidence behind these numbers is genuinely lower for women — not because there's contrary evidence, but because there's less of it.
What that means in practice: the ranges are still the best available guidance, and the studies that have included women haven't found the recommendations need shifting. But anyone claiming precision here is overstating what's known, for either sex.
The bulky question
It's worth addressing directly, because it's the single most common reason women are talked out of eating adequate protein.
Protein doesn't build muscle. Training builds muscle; protein supplies the material. Without a training stimulus, extra protein is simply used for energy or excreted.
And building substantial muscle is difficult on purpose. It requires progressive resistance training sustained over years, alongside a calorie surplus. Women have roughly a tenth to a twentieth the circulating testosterone of men, which makes rapid muscle accrual physiologically implausible. Women who compete in physique sport achieve it through many years of highly deliberate work — it isn't something that happens by accident to someone eating more Greek yoghurt.
The realistic outcome of adequate protein plus resistance training for most women is keeping the muscle they have — which becomes the central issue after 40, and the decisive one after menopause.
Across the menstrual cycle
Protein breakdown appears modestly elevated during the luteal phase, the roughly two weeks after ovulation, along with a small rise in resting metabolic rate. Some researchers suggest slightly higher protein intake during this window.
Honestly assessed, the effect is small, and the difference between a good day and a bad day of eating dwarfs it. If you already hit a consistent daily target, you're covered. This is a detail to be aware of, not a reason to run two different targets.
Appetite changes across the cycle are typically far more consequential than the metabolic ones, and a diet built around adequate protein tends to handle those better, since protein is the most satiating macronutrient.
Pregnancy and breastfeeding
Requirements rise, and this is one of the few areas where official guidance moves meaningfully above the baseline RDA.
- Pregnancy: an additional 25 g per day is the commonly cited figure, concentrated in the second and third trimesters as fetal tissue accumulates.
- Breastfeeding: an additional 25 g per day, to cover the protein secreted in milk.
These are genuine increases with real consequences, and they're also exactly the circumstances where general guidance stops being appropriate. Antenatal care includes nutritional guidance for a reason — use it in preference to a website, this one included.
Menopause, and why it changes the calculation
This is the point in life where protein moves from useful to important.
Oestrogen has a protective effect on both muscle and bone. As it declines, the rate of loss in both accelerates. Muscle mass falls, bone density falls, and the eventual consequences — frailty, fractures, lost independence — arrive decades later, which is precisely why the problem is easy to defer.
Two things demonstrably help, and they work together:
- Resistance training. The signal that tells your body to keep muscle and maintain bone.
- Adequate protein. The material required to act on that signal. Around 1.2–1.6 g/kg is a sensible target, at the higher end if you're training.
Anabolic resistance also becomes relevant — ageing muscle responds less strongly to a given dose — which argues for a decent amount of protein at each meal rather than one large serving at dinner. Roughly 0.4 g/kg per meal, three or four times a day, is the practical version.
Practically
Work out your target from body weight and what you're actually doing, not from a general recommendation aimed at everyone. Then find out what you currently eat, because the gap between assumed and actual intake is usually the entire story — and it's typically 30–50 g wide.
Our protein calculator will give you a number in about a minute. The fortnight of logging afterwards is the part that actually tells you something.
Common questions
How much protein does a woman need per day?
The same grams-per-kilogram figures that apply to men: 0.8–1.0 g/kg for a sedentary adult, 1.4–2.0 g/kg for someone training regularly, and 1.6–2.4 g/kg when dieting to lose fat while keeping muscle. Because women are on average smaller, the resulting gram totals are lower — the multiplier is not.
Will eating more protein make women bulky?
No. Building substantial muscle requires a sustained calorie surplus and years of progressive resistance training, and women have far lower circulating testosterone, which makes rapid muscle gain physiologically unlikely. Protein does not build muscle on its own; it supports the muscle that training stimulates.
Do protein needs change during the menstrual cycle?
Slightly. Protein breakdown appears modestly higher during the luteal phase, the second half of the cycle. The difference is small enough that it does not warrant changing your target — hitting a consistent daily number covers it.
How much protein do women need after menopause?
More, in practice. The decline in oestrogen accelerates muscle and bone loss, so protein and resistance training both become more valuable. Around 1.2–1.6 g/kg is a reasonable target for a healthy postmenopausal woman, rising for those who train.
One number, tracked in seconds
Protein tracking doesn't have to mean logging every calorie and macro. PRO.TEIN tracks one number, turns your year into a calendar of squares, and stays out of the way otherwise.
Where these numbers come from
The core recommendations are the same position stands cited throughout this site: the International Society of Sports Nutrition on protein and exercise, and Morton et al. (2018) in the British Journal of Sports Medicine. Pregnancy and lactation figures follow the US Institute of Medicine's Dietary Reference Intakes and EFSA reference values. The menopause discussion draws on the ESPEN and PROT-AGE guidance on protein in older adults and on published reviews of sarcopenia and bone loss after menopause. The under-representation of women in sports-nutrition research is documented in Costello and colleagues' 2014 analysis in the European Journal of Sport Science.
This is general information, not medical advice. It can't account for your circumstances. If you have kidney or liver disease, diabetes, are pregnant or breastfeeding, or are managing any medical condition, your protein needs may differ substantially — speak to a doctor or registered dietitian before changing your diet.