How Much Protein Should A Woman Eat To Gain Muscle: Advice From A Dietitian

As a registered dietitian, I’m often asked, “What’s the secret to staying strong, fit, and energized?” Well, the answer isn’t a secret at all—protein is the key! Whether you’re lifting weights, chasing after kids, or just trying to feel your best, protein is a game-changer. It’s one of the most important nutrients in your diet, and for women, it plays an even bigger role than you might think. Protein is essential not just for muscle recovery but for building and maintaining muscle mass—especially as we age. So, let’s dive into why protein matters so much for women, how it supports muscle building, and why pairing it with resistance training is a winning combo!

Why Protein is a Big Deal for Women

First things first—protein is your body’s construction material. It helps build and repair tissues, including muscle. Whether you’re lifting weights, doing yoga, or just getting through your day, your muscles are constantly working and constantly being rebuilt. Protein provides the amino acids (the building blocks of muscle) needed for this process.

For women, getting enough protein becomes even more important as we go through life’s changes. From hormonal fluctuations to muscle loss as we age, protein is here to help. As estrogen drops during menopause, the body starts to lose muscle more quickly, so keeping up with protein intake and adding in some resistance training becomes crucial.

Protein and Muscle Building: The Dynamic Duo

When it comes to muscle building, protein alone isn’t enough—it needs a partner. That’s where resistance training comes in. Lifting weights or using your body weight (think squats, lunges, push-ups) creates tiny tears in your muscles. Your body then repairs these tears, making the muscles stronger and bigger. Without enough protein, though, your body won’t have the fuel it needs to repair and build those muscles back up.

As we age, muscle mass and muscle strength naturally declines. After 30, women can lose about 3-5% of muscle mass every decade, and by the time we hit our 60s, that rate can jump to 4-5% per decade, with 9-10% loss each decade in muscle strength. (Yikes, right?) But here’s the good news: Protein and resistance training can slow that process down and even help you build muscle. So, whether you’re a beginner or a seasoned lifter, adding protein and resistance training to your routine is your ticket to keeping that muscle mass intact (and maybe even building a little extra).

The Surprising Role of Protein in Bone Health

While calcium and vitamin D often get all the credit for supporting strong bones, protein plays an equally essential role in maintaining skeletal strength. Bones are made up of roughly 35% collagen, a protein that forms the flexible framework for mineral deposits like calcium and phosphorus. Without adequate protein, collagen synthesis declines, making bones more brittle and vulnerable to fractures — even if calcium intake is sufficient. In fact, protein intake stimulates osteoblasts, the bone-building cells, and increases the production of insulin-like growth factor 1 (IGF-1), a hormone known to promote bone formation. Contrary to outdated myths, current research shows that higher protein intake may actually improve calcium absorption and support bone mineral density, especially when calcium and vitamin D needs are met. Additionally, protein helps preserve muscle mass, which is critical for maintaining bone strength through mechanical loading and reducing fall risk in older adults. According to a 2017 systematic review published in the Journal of the American College of Nutrition, higher protein intake is associated with greater bone mineral density and lower risk of hip fractures, particularly in aging populations (Wallace et al., 2017). To protect your bones long-term, aim for a protein-rich diet that includes sources like lean meats, eggs, dairy, legumes, and collagen-rich foods.

How Much Protein Do You Need?

Now that we know protein is a muscle-building powerhouse and critical for bone health, let’s talk about how much you actually need, depending on your age and activity level. 

The current recommended dietary allowance (RDA) is 0.8 grams of protein per kilogram of body weight. However, most people need quite a bit more than this, especially if engaging in regular physical activity.

Endurance or strength athletes should aim for closer to 1.2 to 2 grams of protein per kilogram of body weight daily. 

Aging women (50+years) or perimenopausal women may need anywhere from 1.2-1.6 grams of protein per kilogram of body weight. For example, someone who weighs 140 lbs or (64 kg) would need anywhere between 77-102 grams of protein daily 

When it comes to protein, there’s no one-size-fits-all approach. Your ideal protein intake is as unique as you are, shaped by factors like your age, activity level, and overall health. That’s why teaming up with a registered dietitian can be a game-changer! They’ll help you determine the right amount of protein to fuel your goals and keep you feeling your best. After all, personalized nutrition is where the real magic happens.

Protein-Packed Sources for Women

Whether you prefer plant-based options or lean animal sources, there are plenty of delicious ways to meet your protein needs. Here are a few of my favorites that you can easily add to your meals:

Animal-Based Protein: Chicken, turkey, lean beef, fish, eggs, Greek yogurt, cottage cheese, and dairy products like milk and cheese.

Plant-Based Protein: If you’re vegetarian or vegan, you’ve got great options too! Try legumes (lentils, chickpeas, beans), tofu, tempeh, edamame, quinoa, nuts, and seeds.

Protein Powders: Sometimes, life gets busy, and you need a quick fix. Protein powders, like whey or plant-based options, are an easy way to meet your protein goals when you’re on the go.

Resistance Training: The Key to Building and Retaining Muscle

You can’t talk about muscle maintenance without mentioning resistance training. Think weightlifting, bodyweight exercises, or using resistance bands. It doesn’t have to mean hitting the gym every day with heavy weights—bodyweight exercises like squats, lunges, and push-ups work wonders too. The key is challenging your muscles enough to create the stress needed for muscle growth.

Resistance training has a ton of benefits for women:

Preserve Muscle Mass: As we age, resistance training helps prevent that age-related muscle loss I mentioned earlier.

Increase Strength: Building muscle improves your overall strength and functional fitness, which can make daily tasks (like carrying groceries or playing with kids or grandkids) feel much easier.

Boost Metabolism: More muscle means a faster metabolism. You’ll burn more calories at rest, which is helpful for weight management

Protein + Resistance Training = Muscle Growth

Here’s the magic formula for building muscle: Resistance training plus protein = muscle growth. It’s that simple! But it’s not just about working out—nutrition plays a huge role in helping your muscles recover and rebuild. Protein is essential for the repair process. Without it, your muscles won’t have the necessary building blocks to recover and grow stronger after each workout. When you engage in resistance training, you create small tears in your muscle fibers. Protein provides the amino acids needed to repair those tears, making the muscle fibers thicker and more resilient. Without sufficient protein, your body can’t efficiently repair or rebuild muscle tissue, which means you may not see the gains you’re working so hard for. So, to maximize your muscle-building efforts, it’s crucial to fuel your body with enough protein both before and after your workouts.

Final thoughts

Incorporating enough protein into your diet, along with regular resistance training, is a powerful strategy for building and maintaining muscle as well as promoting bone health, especially as you age. Protein fuels muscle repair and growth, while resistance training stimulates the muscles to adapt and grow stronger. Together, they help prevent muscle loss, boost metabolism, and improve overall strength and functional fitness. So, whether you’re looking to enhance your workouts or simply maintain a healthy body as you age, focusing on adequate protein intake and resistance training is key. Start today, and you’ll be well on your way to preserving muscle mass, improving strength, and feeling your best at every stage of life.