How Much Protein Should a Woman Eat Per Day?

Marika is 38 and has been vegetarian since university. She lifts twice a week and is not trying to lose a kilo. She arrived with three numbers for how much protein per day she should eat: her gym app said 130 g, a podcast said 60 g was plenty, and a friend who had just started lifting told her 2 g per kilo. The number on app was never explained to her. So she had quietly stopped trying to hit any of them.

Marika's problem was not that she had no information. She had too much of it, from sources that each gave her a single figure and none of which told her where it came from. That is the ordinary situation. Almost every woman who asks me this question has been handed one number by someone, and it is usually either the floor dressed up as a target, or a bodybuilder's target handed to a woman who lifts twice a week and has no interest in competing.

So this article does the arithmetic in the open. By the end you should have a figure written down for yourself, adjusted for whichever of the situations below is actually yours.

01

The two numbers: the floor and the target

The Recommended Dietary Allowance for protein, set by the National Academies in the United States and echoed by most national guidelines, is 0.8 g per kg of body weight, or 0.36 g per lb. That figure has not changed. What it is, though, is a floor: the amount estimated to meet the basic needs of almost all healthy adults, derived from nitrogen balance studies, designed to prevent deficiency. It was never meant as the amount that keeps muscle on a 48-year-old or stops you raiding the cupboard at nine in the evening.

Research over the past two decades has consistently found benefits above that floor for muscle maintenance and for ageing with your strength intact. Which is why most practitioners, including me, work from a target range of roughly 1.2 to 1.6 g per kg for women, and from the top of it or above for women who lift.

Both halves of that are honest and they are not in conflict. The RDA is not wrong; it answers a different question. "What stops a healthy adult going into protein deficit?" has a lower answer than "What keeps a woman's muscle and her appetite where she wants them?"

Worth saying plainly, because I have seen it circulating: the official RDA has not been raised to 1.2 or 1.6 g per kg. It is still 0.8. The higher figures are what research and clinical practice support for specific goals and groups, which is a different kind of claim and a weaker one. I would rather you knew which was which than believed a stronger version that is not true.

02

Work out how much protein per day you need, in about a minute

The calculation is body weight in kilograms multiplied by the number you have chosen from the range. Weight in kg times 1.2 gives the lower end of the target, times 1.6 the upper. In pounds, multiply by 0.55 and 0.73 for the same range, or by 0.36 for the floor. That is the whole arithmetic, and it is worth doing yourself once so the number stops being something an app told you.

One caveat on the arithmetic. If you are carrying a lot of excess weight, running the multiplier on your current weight gives a figure that is higher than you need, because the extra fat tissue does not have protein requirements the way muscle does. In that case the calculation is usually done on a goal weight or an adjusted weight, and the honest answer is that this is the point to get individual advice rather than pick a number off a blog, mine included.

03

When the target moves up

Four situations push your figure toward the top of the range or past it: strength training, being over 40, eating in a calorie deficit, and pregnancy or breastfeeding. None of them push it down. That asymmetry surprises women who assume protein needs shrink as life gets less athletic, and it is the single most common correction I make.

If you strength train two or three times a week

Work toward 1.6 g per kg rather than 1.2, because after a session the protein has a job to do beyond maintenance. Morton and colleagues pooled 49 trials for the British Journal of Sports Medicine in 2018 and found that extra protein improved strength and lean mass gains from resistance training, with the benefit flattening out at around 1.6 g per kg a day. Their uncertainty stretched up to roughly 2.2, so there is room above it, but 1.6 is where the clear return stops. Marika lifting twice a week is exactly this case, which is why her figure landed near 90 rather than 75.

If you are over 40 or in perimenopause

Your target goes up, not down. Muscle becomes less responsive to the same dose of protein with age, something researchers call anabolic resistance, so the same 20 g of protein builds less than it did at 25. Add the muscle loss that accelerates through the forties and the oestrogen changes of perimenopause, and protein stops being optional. I cover the fuller picture in how to lose weight after 40, and the hormonal side in the perimenopause diet article.

If you are eating in a calorie deficit

Protein needs go up while total food goes down, which is the squeeze most diets get badly wrong. When energy is short, the body is more willing to break down muscle, and protein is what argues against that. So a woman cutting calories should be at the top of her range or slightly above, not cutting protein along with everything else. The full weight-loss case for protein, including the satiety hormones and the thermic effect that I am deliberately not re-explaining here, is in the protein for weight loss guide.

If you are pregnant or breastfeeding

Needs genuinely rise, in both pregnancy and lactation, and they rise by different amounts at different stages. I am not going to put a target range here, because this is a figure that belongs to your midwife or doctor, who knows your stage and your medical history. Ask them for your number. Do not scale a general range and hope.

04

Protein intake for women over 50 and over 60

After 50 the target rises again, and after 60 it matters more than at any other stage. The PROT-AGE expert group, led by Bauer and published in the Journal of the American Medical Directors Association in 2013, recommended at least 1.0 to 1.2 g per kg for healthy older adults, with more for those who exercise or who are managing illness or weight loss. In my own practice I work from 1.2 to 1.6 g per kg for this group, which at 65 kg (143 lb) comes to 78 to 104 g a day.

What makes this group different is how under-eating protein shows up. It is not a number on the scale. It is a handrail that becomes necessary on the stairs, or a jar lid that will not open. Muscle lost slowly over a decade does not announce itself until it is the thing stopping you doing something you used to do without thinking.

The other difference is appetite. Many women in their sixties and seventies are simply eating less food than they used to, and a smaller plate with the same proportions means less protein. This is the group where I most often suggest a dairy-based or egg-based anchor at breakfast specifically, because that is the meal where intake has quietly collapsed.

05

Vegetarian and vegan: the number sits higher and needs planning

If you do not eat meat or fish, your practical target sits somewhat higher than the 1.2 to 1.6 g per kg range, because plant proteins are less concentrated per portion and generally less well used by the body, with lower levels of some of the amino acids muscle needs most. Variety across the day matters more than any single food. This is not a problem, but it is a thing you have to do on purpose.

Here is where Marika had gone wrong, and it is the most common vegetarian error I see. She was eating lentils most days and thought that is enough. Lentils are a good food. They are also about 9 g of protein per 100 g cooked, so a generous serving in a soup gives her maybe 15 g, which she had been mentally counting as "a protein meal". Her words on the second call: "So the beans were never the main thing. They were the side thing that I called the main thing."

The real numbers, so you can do your own counting:

Marika's 90 g is reachable without much drama: skyr with almonds at breakfast gets her to 28, a lentil and feta lunch at a serious portion size adds about 32, Greek yoghurt in the afternoon another 14, and 100 g of tempeh at dinner brings the day to roughly 93. Four anchors rather than four sides.

06

What 100 g of protein actually looks like

A day landing near 100 g is four eating occasions with a protein anchor in each, and it does not look like a bodybuilder's meal prep. Roughly 25 to 30 g at each main meal and 15 at one snack gets you there. Writing it out like this is the fastest way to see whether your figure is realistic for how you actually eat.

That comes to roughly 102 g, which is the target for a 70 kg (154 lb) woman near the middle of her range. Nothing in it is a powder or a bar. If your figure is 70 g rather than 100, the same four occasions with slightly smaller anchors get you there, and you can drop the afternoon one.

07

Is 100 g of protein too much for a woman?

For most women, no. At 70 kg (154 lb), 100 g sits comfortably inside the 84 to 112 g target, and there is no evidence that intakes in this range harm healthy women. More is not linearly better, though. Above roughly 2 g per kg the evidence for additional benefit thins out for most women, and the extra protein starts crowding out the vegetables and fibre that your gut and your cholesterol care about. That displacement is the real cost of overshooting, not some direct harm from the protein itself.

The kidney question comes up in almost every consultation, usually in the form "but is it bad for my kidneys?" In healthy women, higher protein intakes within the ranges in this article have not been shown to damage kidney function. The idea that they do comes from advice given to people who already have kidney disease, where protein restriction is a genuine treatment. If you have kidney disease, or any medical reason you have been told to limit protein, your figure comes from your doctor and not from this page. I would not adjust it based on anything I have written here.

The one group I do slow down with is women who have decided to chase 2 g per kg because the internet is in a protein phase. At 70 kg that is 140 g, which is achievable but starts to dictate the whole plate. If you want it, have it. Just notice what left the plate to make room.

08

What too little protein looks like

Not dramatic deficiency, which is rare in countries where food is plentiful, but a quieter version that gets blamed on other things. Hunger that comes back an hour after you ate. Strength that stops improving even though you keep showing up at the gym. Hair and nails that have changed. And, during weight loss, a scale that moves while your shape does not, because what left was lean tissue rather than fat.

The women who come to me are usually eating somewhere between 50 and 70 g of protein a day and are convinced they eat plenty of it. Their target is almost always between 85 and 110 g. That gap of 30 or 40 g is the whole conversation, and it closes with two or three changes rather than a new diet.

The satiety half of this, why a low-protein day leaves you hungry on the same number of calories, is covered in how to lose weight without feeling hungry. Leidy and colleagues reviewed the weight-management evidence for the American Journal of Clinical Nutrition in 2015 if you want the research version.

Marika, for what it is worth, has not got to 90 g yet. She is somewhere in the seventies most days, which is already 20 g more than when she started, and she has stopped treating a bowl of lentil soup as a protein meal. The three numbers she arrived with are still in her phone. She just knows now which one was a floor and which one was someone else's target, and roughly where her own figure sits.