Ask ten different people how much protein you need and you’ll get ten different answers. Ask your doctor, and they’ll probably quote a number that was set decades ago for sedentary men. Here’s what the current research actually says — specifically for women over 40.
Why the standard advice is wrong for you
The official recommended dietary intake (RDI) for protein in Australia is 0.75g per kilogram of bodyweight per day for adult women. For a 65kg woman, that’s about 49g of protein daily — roughly the amount in two chicken breasts.
Here’s the problem: that number was designed to prevent deficiency in the general population. It was not designed to help women over 40 preserve muscle mass, support hormone production, recover from exercise, maintain bone density, or feel energised and satiated throughout the day.
For active women in midlife, current sports nutrition and gerontology research points to a target that’s roughly double the official RDI — and for good reason.
What happens to protein in your body after 40
There’s a phenomenon called anabolic resistance that becomes increasingly relevant as we age. In simple terms, your muscles become less responsive to protein as you get older. Where a younger woman might build muscle effectively from 20g of protein at a meal, an older woman may need 35–40g to get the same muscle-building signal.
At the same time, declining oestrogen affects how efficiently your body uses the protein you consume. Oestrogen plays a role in muscle protein synthesis — the process of converting dietary protein into actual muscle tissue. As levels drop, you need more protein input to get the same output.
Add to this the fact that protein also supports:
- Bone density — protein provides the matrix on which calcium is deposited
- Immune function — antibodies are made from protein
- Hormone production — many hormones are protein-based
- Satiety — protein is the most filling macronutrient, reducing cravings and overeating
- Metabolism — protein has a high thermic effect, meaning your body burns more calories digesting it
The case for prioritising protein after 40 is overwhelming.
So how much do you actually need?
Current research for active women over 40 consistently points to a target of 1.6–2.2g of protein per kilogram of bodyweight per day.
Here’s what that looks like in practice:
| Bodyweight | Minimum (1.6g/kg) | Optimal (2.0g/kg) |
|---|---|---|
| 55kg | 88g/day | 110g/day |
| 65kg | 104g/day | 130g/day |
| 75kg | 120g/day | 150g/day |
| 85kg | 136g/day | 170g/day |
These numbers feel high to most women at first — because they are significantly higher than what we’ve been told to aim for. But they are well within safe ranges and supported by robust research in older adults.
Want your exact number? Use our free protein calculator at OmniCalcFit — built specifically for women in midlife.
Does it matter when you eat protein?
Yes — and this is where most women leave significant results on the table.
Research shows that spreading protein evenly across meals is far more effective for muscle protein synthesis than consuming most of your protein in one sitting. Aim for 30–40g per meal, three to four times per day, rather than a small breakfast, a small lunch, and one large protein-heavy dinner.
This matters because there’s an upper limit to how much protein your body can use for muscle building at any one time — roughly 40g per meal. Anything beyond that at a single sitting is used for energy or excreted, not muscle building.
Practical meal structure for 130g protein daily:
- Breakfast: 35g protein
- Lunch: 35g protein
- Dinner: 40g protein
- Snack: 20g protein
The best protein sources for women over 40
Not all protein is created equal. For muscle building and maintenance, you want sources rich in leucine — the amino acid that most powerfully triggers muscle protein synthesis.
The best leucine-rich sources include:
- Animal proteins: chicken breast, salmon, tuna, eggs, Greek yoghurt, cottage cheese, lean beef, turkey
- Dairy: milk, cheese, whey protein (one of the highest leucine sources available)
- Plant proteins: tofu, tempeh, edamame, lentils, chickpeas — note these need to be consumed in larger quantities to match the leucine content of animal sources
If you eat a plant-based diet, you can absolutely meet your protein needs — it just requires more planning and variety. Combining different plant proteins (legumes with grains, for example) improves the overall amino acid profile.
What about protein supplements?
Protein supplements — particularly whey protein — can be a convenient and effective way to hit your daily targets, especially if you’re training regularly. They’re not magic, but they’re also not harmful. They’re simply a concentrated food source.
A good quality whey protein isolate provides 25–30g of high-leucine protein per serve with minimal fat and carbohydrates. If you’re plant-based, pea protein combined with rice protein provides a complete amino acid profile.
That said, whole food sources should always be your foundation. Supplements fill gaps — they don’t replace meals.
Practical ways to eat more protein without obsessing over food
The biggest barrier most women face isn’t knowledge — it’s practicality. Here are simple strategies that work:
- Protein-anchor every meal. Before building the rest of your plate, ask: where is my protein coming from? Then build around it.
- Greek yoghurt is your friend. 170g of plain Greek yoghurt provides 17g of protein. Add it to breakfast, use it as a snack, mix it into sauces.
- Eggs at breakfast. Three eggs provide 18g of protein. Pair with smoked salmon and you’re at 30g before 9am.
- Batch cook proteins. Grill chicken, hard boil eggs, or cook a batch of lentils at the start of the week so high-protein options are always accessible.
- Don’t fear cottage cheese. Half a cup provides 14g of protein and works in sweet or savoury contexts.
The bottom line
The standard protein recommendations are not adequate for women over 40 who want to preserve muscle, support their metabolism, and feel strong and energised. Aim for 1.6–2.0g of protein per kilogram of bodyweight daily, spread evenly across meals, from high-quality sources.
It’s one of the highest-return dietary changes you can make in midlife — and unlike most nutrition advice, it’s backed by decades of solid research.
Start tracking your protein for one week. Most women are shocked to discover how far below their optimal target they’ve been — and how much better they feel once they address it.
Find your exact protein target with our free protein calculator at OmniCalcFit — no sign-up needed.
Want a personalised nutrition and workout plan? The Fit & Flourish app is built specifically for women over 40, with meal tracking, AI photo scanning, and adaptive workout programming. Try it free today.