Why the standard RDA isn't enough
The 0.8g/kg RDA represents the minimum to prevent deficiency in sedentary adults — not the optimal amount for health, muscle maintenance, or aging well. For women over 40, several physiological changes make higher protein intake significantly more important.
What changes after 40
Sarcopenia: the silent muscle thief
From around age 30, muscle mass begins to decline at roughly 3–8% per decade. After 60, this accelerates. This process — sarcopenia — directly affects your metabolism, strength, bone density, and long-term independence. Protein is the primary dietary tool to slow it down.
Anabolic resistance
Older muscles don't respond to protein the same way younger muscles do. A phenomenon called anabolic resistance means you need a higher dose of protein per meal — typically 30–40g rather than 20–25g — to trigger the same muscle protein synthesis response. This has significant implications for how much total protein you need each day, and how you spread it across meals.
Hormonal shifts: perimenopause and menopause
Estrogen has a protective effect on muscle tissue. As estrogen declines during perimenopause and drops significantly post-menopause, muscle loss accelerates and body fat redistribution becomes more pronounced. Post-menopausal women have particularly elevated protein needs compared to premenopausal women of the same weight and activity level.
What the research recommends
Most sports nutrition and gerontology research now recommends 1.2–1.6g of protein per kg of body weight for active women over 40 — roughly double the standard RDA. For post-menopausal women or those doing regular resistance training, 1.6–2.0g/kg may be even more appropriate.
Get your personalised protein target based on your age, weight, and menopausal status.
Calculate my protein needs →Practical protein targets by life stage
Women in their 40s (premenopausal)
Aim for 1.2–1.5g/kg. At this stage, the focus is on maintaining muscle mass and metabolic health. Regular resistance training paired with adequate protein is your best defence against the muscle loss that accelerates in later decades.
Women in perimenopause
Estrogen fluctuations during perimenopause accelerate muscle loss. This is a critical window to increase protein intake. Aim for 1.4–1.7g/kg, with particular attention to spreading protein evenly across meals rather than concentrating it at dinner.
Post-menopausal women
Research supports higher targets at this stage — 1.5–2.0g/kg — to counteract the loss of estrogen's protective effects on muscle. Combining higher protein intake with resistance training at least 2–3 times per week is the most effective approach to preserving muscle and managing body composition.
The meal distribution problem
Due to anabolic resistance, distributing protein evenly across 3–4 meals matters more than total daily intake alone. Eating 120g of protein in two large meals is less effective than spreading it across three meals of 40g each. Every meal is an opportunity to stimulate muscle protein synthesis — don't waste meals with low-protein options.
Best protein sources
- Eggs: Complete amino acid profile, high bioavailability, leucine-rich. 6g per egg.
- Greek yogurt: 15–20g per serving, convenient, high in calcium for bone health.
- Chicken breast: ~31g per 100g, lean, versatile.
- Salmon and other fatty fish: High protein plus omega-3s, which have independent anti-inflammatory benefits.
- Cottage cheese: High in casein (slow-digesting), great before bed.
- Legumes: 15–18g per cup cooked. Lower bioavailability than animal protein, but valuable when combined throughout the day.
- Protein supplements: Whey, casein, or plant-based protein powders can help fill gaps, especially post-workout.