Protein is everywhere right now. You can’t escape it.

Our cultural ideal has shifted from skinny to lean and toned. We now celebrate strength training, muscle, and performance as the goal. And protein has been framed as the essential ingredient to get there.

The rise of GLP-1s has added another angle: preserving lean muscle while rapidly losing weight is now a real clinical concern.

Honestly, this shift has mostly sounded good to me. Pushing protein seems like a healthy cultural advancement, even if the reasons behind it feel more like marketing than medicine.

But is that the case? What I want to know is: what is protein actually doing for me, physiologically? How much do I really need, not to hit a fitness aesthetic, but to be healthy? And beyond muscle, what else does adequate protein ensure for my body?

That’s my real question this week. Not how to get toned, but what does protein actually do, and how much of it do I genuinely need?

Studies show that we need more than most of us are getting. And for more reasons than muscle. It’s not all marketing.

The standard recommendation for adult women is 0.8 g of protein per kg of body weight per day. For a 65 kg / 140 lb woman, that’s about 52 g: roughly two chicken breasts. But that number is increasingly considered a floor, not a target. And depending on your life stage, even that may not be enough.

We talk a lot about our muscles. Yes, protein builds and maintains muscle.

But it also:

Perhaps it’s unsurprising, but when we talk about protein, we’re not only talking about aesthetics. It’s the basics of physiological function. And we need lots of it.

The 0.8 g/kg standard was set for general healthy adults.

But research using more precise measurement methods suggests women need more.

And of course, our needs shift significantly across life stages.

General adult women: 0.8–1.0 g/kg per day is a reasonable baseline.

Active women: 1.3–1.8 g/kg per day to support training and recovery. Higher activity means higher breakdown, and you need more protein to keep up.

Pregnant women: Standard guidelines say 1.1 g/kg, but direct measurement studies put early pregnancy needs closer to 1.2 g/kg and late pregnancy closer to 1.5 g/kg.

Breastfeeding women: Around 1.7-1.9 g/kg per day in early postpartum. This is nearly double the general recommendation!! Milk production is expensive.

Perimenopausal and postmenopausal women: At least 1.0–1.2 g/kg per day. Falling estrogen creates what researchers call "anabolic resistance." Our muscles become less responsive to protein, so we need more of it to maintain the same muscle mass.

Slightly, but not dramatically. We use amino acids (which we get from our protein intake) more intensively in the two weeks before our periods. This is why some of us find that we naturally tend to eat more protein during this time.

If you notice more hunger or cravings in the second half of your cycle, adding protein sources makes sense.

GLP-1s suppress appetite significantly, reducing overall food intake and therefore, protein intake alongside it. Up to 50% of weight lost on GLP-1s can be lean muscle mass, not just fat. Given what protein does for us beyond muscle, higher protein intake isn’t optional on GLP-1s.

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How to figure out for yourself if you’re getting enough? Start here:

🥩 Figure out your number.
Take your weight in kg and multiply by 0.8 for a minimum (~0.4 g/lb), or 1.5 if you're pregnant or breastfeeding (~0.7 g/lb).

⏰ Add protein to your next meal.
Aim for 25–40 grams at each meal. A palm-sized piece of chicken or fish gets you there. Otherwise, combine sources: two eggs plus Greek yogurt, or cottage cheese with a handful of nuts.

📍 Pregnant, breastfeeding, or in perimenopause? Your protein needs just went up.
Aim for at least 1.5 g/kg daily, nearly double the standard recommendation. Start by adding a palm-sized portion of meat, fish, or legumes to every meal this week.