Why Women Over 40 Need More Protein

Aging gracefully is not just about how you look. It is about how strong and capable you feel every single day -- carrying groceries, climbing stairs, playing with your kids or grandkids, and living without the fear of injury.

For many women, the years around menopause bring unexpected challenges. One of the biggest is the quiet, steady loss of muscle that begins accelerating in your 40s. It does not always show up right away, but over time it chips away at your strength, your energy, and your independence.

After working with hundreds of clients over two decades, I can tell you that the single most impactful change women over 40 can make is increasing their protein intake. This is not about bodybuilding. It is about maintaining the body you need to live the life you want. And the science backs this up powerfully.

Why Does Muscle Loss Accelerate After 40?

Menopause is a turning point for women's health -- not just hormonally but physically. One of the most significant changes is the acceleration of age-related muscle loss, clinically known as sarcopenia.

This happens for two interconnected reasons:

Hormonal shifts. Estrogen plays a direct role in regulating muscle repair, protein utilization, and inflammation. As estrogen levels decline during perimenopause and menopause, the body breaks down muscle more easily and takes longer to recover from exercise and daily activity.

Anabolic resistance. This is a concept that most women have never heard of, but it is central to understanding why protein needs change with age. Research published in *Nutrients* explains that aging creates "anabolic resistance" -- a blunted muscle protein synthesis response to protein ingestion. In practical terms, this means your muscles become less responsive to the protein you eat. Where a 25-year-old might maximally stimulate muscle building with 20 grams of protein, an older adult needs significantly more to achieve the same response (Stokes et al., 2018).

A 2024 study confirmed this directly in postmenopausal women: 15 grams of whey protein, sufficient to trigger muscle protein synthesis in younger women, did not produce the same response in postmenopausal participants (Smith et al., 2024). The message is clear -- the protein amounts that worked in your 20s and 30s are no longer enough.

Women over 50 can lose muscle mass at a faster rate than men of the same age. This decline not only reduces strength but also affects energy, balance, and bone density, increasing the risk of falls, fractures, and frailty.

How Much Protein Do Women Over 40 Actually Need?

Most people are familiar with the Recommended Dietary Allowance (RDA) for protein, which is set at 0.8 grams per kilogram of body weight per day. But this number was established to prevent deficiency in the general population -- it was never designed for optimal health in aging adults.

The international PROT-AGE Study Group published evidence-based recommendations in the *Journal of the American Medical Directors Association* that challenge this outdated guideline. Their recommendation: healthy older adults need at least 1.0 to 1.2 grams of protein per kilogram of body weight daily -- 25% to 50% more than the standard RDA. Those with acute or chronic illness need 1.2 to 1.5 g/kg/day. Per-meal recommendations are 25-30 grams of high-quality protein containing 2.5-2.8 grams of leucine (Bauer et al., 2013).

For a 65 kg (143 lb) woman, that translates to:

• RDA (minimum): 52g protein/day
• PROT-AGE recommendation: 65-78g protein/day
• Per meal target: 25-30g, three to four times daily

Research on dose response in older adults reinforces this. A study in the *American Journal of Physiology* found that ingestion of 35 grams of whey protein resulted in greater amino acid absorption and muscle protein synthesis stimulation compared to 10 or 20 grams in adults over 70, suggesting older adults benefit from higher protein doses per serving than is commonly recommended (Pennings et al., 2012).

However, the reality is that many women do not even reach the baseline RDA. A study of post-menopausal women aged 60-90 found that one in four women consumed insufficient protein (Gregorio et al., 2014). That is a significant shortfall with real consequences.

What Happens When Post-Menopausal Women Eat More Protein?

The same study by Gregorio and colleagues, published in the *Journal of Nutrition, Health & Aging*, found that post-menopausal women consuming higher protein (averaging 1.1 g/kg/day) had significantly lower body fat, better body composition, and superior physical performance compared to those eating below the RDA (Gregorio et al., 2014).

The benefits of increasing protein intake above the minimum are substantial:

• Stronger muscles: Preserved lean mass supports daily activity and protects bones and joints.
• Better body composition: Higher protein intake is consistently associated with lower body fat percentages and more favorable lean-to-fat ratios.
• Improved functional performance: Walking speed, grip strength, balance, and overall independence are all positively associated with adequate protein intake.
• Bone density support: Protein contributes to bone matrix formation, reducing the risk of osteoporosis -- a major concern for post-menopausal women.
• Enhanced recovery: Whether from exercise, illness, or injury, adequate protein accelerates the body's repair processes.

Can Sarcopenia Be Reversed?

Yes. The good news is that muscle loss is not entirely inevitable. While sarcopenia is a natural part of aging, it can be significantly slowed and, in many cases, partially reversed. Researchers consistently highlight two key tools:

Protein intake above the RDA. The largest meta-analysis on protein and muscle gain, published in the *British Journal of Sports Medicine*, found that protein supplementation significantly increases fat-free mass and strength during resistance training. Benefits plateaued at approximately 1.6 g/kg/day (Morton et al., 2018). For women over 40 dealing with anabolic resistance, aiming for the upper end of the PROT-AGE recommendations (1.2 g/kg/day) is a strong starting point.

Resistance training. This amplifies the protein effect by directly stimulating muscle fibers to grow stronger and adapt. Even simple routines with light weights, resistance bands, or bodyweight movements can make a noticeable difference. The combination of adequate protein and resistance training is far more effective than either intervention alone.

Practical Tips: How to Hit Your Protein Targets

Reaching higher protein targets does not require a diet overhaul. Small, consistent changes add up:

Breakfast (Target: 25-30g protein)

• Three eggs with vegetables on whole-grain toast (21g + bread protein)
• Greek yogurt (170g) with nuts and seeds (20-25g)
• Protein smoothie with whey, berries, and oat milk (30g)

Lunch and Dinner (Target: 25-30g each)

• Palm-sized portion of fish, chicken, or legumes at every meal
• Add beans or lentils to soups and salads for an extra 8-15g

Snacks and Supplements

• A clean whey protein shake between meals is a simple, reliable way to close the gap -- especially on busy days when meal prep is not an option.
• Look for a single-ingredient, grass-fed whey with no artificial sweeteners or fillers, providing at least 25g of protein per serving.

The key is distributing protein across the day rather than loading it all into dinner. Your muscles can only process so much at once, and spreading intake across three to four meals ensures a more consistent anabolic stimulus.

The Bottom Line

Aging does not have to mean losing strength, independence, or vitality. The science is unambiguous: women over 40 need more protein than the standard RDA suggests, and the consequences of falling short are real -- from accelerated muscle loss to increased fracture risk.

By focusing on 1.0 to 1.2 grams of protein per kilogram daily, distributing 25-30 grams across each meal, and pairing nutrition with regular resistance training, women can meaningfully reduce the impact of sarcopenia and continue living with strength and confidence.

If you are on GLP-1 medications like Ozempic or Wegovy, the protein conversation becomes even more urgent. Our GLP-1 friendly protein snacks guide covers exactly how to protect muscle mass while on these medications.