Can you build muscle on 50g protein a day?

October 9, 2025 •

4 min read

For individuals regularly engaging in strength training, studies show that the optimal protein intake for building and maintaining muscle is significantly higher than the standard dietary allowance, with most research recommending a range of 1.4–2.0 grams per kilogram of body weight. This means building significant muscle mass on just 50g of protein a day is highly improbable for the majority of people.

Quick Summary

Building substantial muscle mass on only 50g of protein daily is largely ineffective for active individuals, as optimal protein intake for muscle growth is much higher. Insufficient protein compromises the body's ability to repair muscle and can lead to stalled progress.

Key Points

50g is Insufficient: For most active people, 50g of protein is not nearly enough to support optimal muscle growth and can lead to stalled progress.
Optimal Range is Higher: Strength-training individuals should aim for 1.4 to 2.0 grams of protein per kilogram of body weight daily for efficient muscle synthesis and repair.
Low Protein Causes Muscle Loss: When protein intake is inadequate, the body may break down muscle tissue to get the amino acids it needs for other functions, leading to muscle loss.
Combine with Training: A high-protein diet is ineffective for building muscle without a consistent and progressive resistance training program to stimulate growth.
Distribute Protein Strategically: Spreading protein evenly across meals (e.g., 20-40g per meal) can optimize muscle protein synthesis throughout the day.
Quality Matters: Prioritize complete, high-quality protein sources like lean meats, dairy, eggs, and soy to ensure you receive all essential amino acids.
Hydration is Critical: Staying adequately hydrated is vital for muscle recovery and metabolic processes, especially on a higher protein diet.

Understanding the Role of Protein in Muscle Growth

Protein is often called the 'building block' of muscles for a good reason. When you engage in resistance training, you create microscopic tears in your muscle fibers. The body uses amino acids from dietary protein to repair these fibers, making them stronger and larger in a process known as muscle protein synthesis (MPS). Without adequate protein, this repair process is hampered, and muscle growth is limited or even reversed.

Why 50g of Protein Is Insufficient for Most Active Individuals

The misconception that a low protein intake is enough to build muscle often stems from a misunderstanding of basic dietary recommendations versus the specific needs of an athlete. The Recommended Dietary Allowance (RDA) of 0.8 grams per kilogram of body weight is designed to prevent deficiency in sedentary individuals, not to optimize muscle growth in active ones. For anyone pursuing muscle hypertrophy, or growth, a 50g intake is far below the requirements.

The Recommended Daily Allowance vs. Athletic Needs

RDA for Sedentary Adults: At 0.8 g/kg, a 75kg (165 lb) sedentary person needs approximately 60g of protein per day. A 50g intake is even less than this base requirement for many average-sized adults.
For Active Individuals: For those who exercise regularly, requirements increase to 1.1–1.5 g/kg. For a 75kg person, this is 82.5–112.5g. Strength athletes need even more, typically 1.6–2.2 g/kg, which is 120–165g for the same individual.

The Impact of Low Protein on Muscle Repair

When protein intake is too low, the body enters a state of negative nitrogen balance, meaning muscle protein breakdown outpaces synthesis. This not only stalls muscle growth but can lead to muscle loss over time, especially during calorie restriction or intense training periods.

The Risk of Muscle Loss (Sarcopenia)

In older adults, there is a natural decline in muscle mass known as sarcopenia. This effect is amplified by inadequate protein intake, as the body becomes less responsive to the anabolic effects of protein. A low protein diet of 50g would exacerbate this issue and lead to significant muscle loss. While less dramatic, even younger, active individuals will experience a lack of progress and potentially muscle atrophy on such a limited intake.

Practical Ways to Increase Protein Intake

Boosting your protein intake doesn't have to be complicated. Here are some strategies to integrate more high-quality protein into your daily diet:

Prioritize Protein at Every Meal: Aim for a protein source at each meal and snack. This not only helps you meet your daily goal but also helps stimulate MPS throughout the day.
Include High-Protein Snacks: Replace low-protein snacks like chips or crackers with options like a handful of almonds, Greek yogurt, or a piece of cheese.
Use Protein Supplements: Protein powders can be a convenient and quick way to increase your intake, especially post-workout. Options like whey or casein can provide a concentrated dose of protein without adding excessive calories.
Boost with Everyday Add-ins: Mix powdered milk or protein powder into oatmeal, mashed potatoes, or soups. Add nuts and seeds to salads, cereals, and yogurt for an easy protein increase.

Comparison Table: 50g vs. Optimal Protein Intake


Feature	50g Protein Intake	Optimal Protein Intake (e.g., 120-165g)
Muscle Growth Potential	Very low to non-existent for most active people; may cause loss.	High, supporting consistent muscle hypertrophy with resistance training.
Muscle Repair & Recovery	Inadequate, leading to delayed recovery and persistent soreness.	Efficient, allowing for faster muscle repair and reduced soreness post-workout.
Satiety Levels	Lower protein leads to lower satiety, potentially increasing overall caloric intake.	Higher protein promotes fullness and can aid in weight management.
Body Composition	Ineffective for building muscle; may contribute to loss of lean mass.	Promotes gain of lean body mass while minimizing fat gain, especially during a caloric surplus.
Overall Energy	May lead to fatigue as protein isn't used optimally and can be burned for energy.	Supports sustained energy levels, especially when paired with adequate carbs.

Conclusion: The Bottom Line on Protein for Muscle Growth

The notion that you can effectively build muscle on 50g of protein a day is a myth for the majority of active individuals. For optimal muscle growth and maintenance, protein intake must be significantly higher and paired with a consistent resistance training program. A balanced, protein-rich diet is essential for stimulating muscle protein synthesis, repairing tissue damage, and ensuring your hard work in the gym translates to tangible results. Trying to build muscle on a low protein diet will leave your body without the necessary building blocks, leading to frustration and minimal progress. Consulting a registered dietitian can provide personalized guidance to help you find the right amount of protein for your specific body and goals. The evidence is clear: when it comes to muscle, you need to fuel your body appropriately for growth.

Practical Steps for Fueling Your Gains

Determine Your Needs: Calculate your target protein intake using the 1.6–2.2 g/kg range based on your body weight and goals.
Plan Your Meals: Incorporate high-quality protein sources like lean meats, dairy, and legumes into every meal to consistently supply your muscles with amino acids.
Time Your Intake: Consider consuming a quality protein source within the four to six hours surrounding your workout to optimize muscle synthesis.
Combine with Resistance Training: Remember that protein intake is only part of the equation. Progressive resistance training is the key stimulus for muscle growth.
Stay Consistent: Consistency in both your training and nutrition is far more important than any single protein-rich meal. Focus on creating a sustainable, high-protein diet plan. For additional resources on increasing protein intake, see Healthline's guide on 15 Easy Ways to Increase Your Protein Intake.

Frequently Asked Questions

For most individuals engaged in strength training, the optimal protein intake for muscle building is between 1.4 and 2.0 grams per kilogram of body weight per day.

If you don't consume enough protein, your body will struggle to repair and rebuild muscle tissue, leading to slowed progress, prolonged soreness, and potential muscle loss.

While protein powders can be a convenient supplement, it is best to prioritize whole food sources of protein first. A balanced diet with various high-quality protein foods provides a wider range of nutrients.

Distributing your protein intake evenly across meals throughout the day is more effective for promoting greater muscle protein synthesis compared to consuming it all at once.

For a very light, sedentary individual (e.g., 50kg), 50g of protein might meet basic needs. However, for anyone actively training to build muscle, this amount is still likely too low for optimal results.

Excellent sources include lean meats, fish, eggs, dairy (like Greek yogurt and cottage cheese), legumes, nuts, seeds, and soy products like tofu and edamame.

In healthy individuals, high protein intakes (up to 2 g/kg/day) are generally safe. However, excessive amounts can place a strain on the kidneys for those with pre-existing kidney conditions. It's always best to consult a healthcare professional.

While there is a post-workout anabolic window, recent research suggests that overall daily protein intake is more important than timing. Consuming protein within four to six hours before or after training is considered effective.