What happens if you eat 50 grams of protein a day? A deep dive into your body's needs

October 9, 2025 •

3 min read

For the average, sedentary adult, the Recommended Dietary Allowance (RDA) for protein is 0.8 grams per kilogram of body weight, which for a 140-pound person is approximately 50 grams of protein a day. However, this amount is simply the minimum required to prevent deficiency and may not be sufficient for everyone, especially those with specific health goals or higher activity levels.

Quick Summary

The effect of consuming 50 grams of protein daily is highly individual, depending on your weight, activity level, and health goals. It is generally adequate for a sedentary person but may be too low for athletes or those aiming for muscle growth, potentially leading to muscle mass loss and other symptoms of under-consumption. The optimal intake varies significantly, making a one-size-fits-all approach insufficient.

Key Points

RDA and Sedentary Needs: For a sedentary person, 50 grams of protein per day meets the RDA of 0.8 grams per kilogram of body weight, but may not be optimal.
Active Individuals Need More: People who are physically active or resistance training require significantly more protein, often 1.6-2.2 grams per kilogram of body weight, making 50 grams insufficient for muscle growth and recovery.
Protein Needs Increase with Age: Older adults need a higher protein intake (1.2-1.6 grams per kilogram) to combat age-related muscle loss (sarcopenia), so 50 grams is likely too low for this demographic.
Consequences of Insufficient Intake: Consistently eating too little protein can lead to muscle mass loss, slowed recovery, weakened immunity, and fatigue.
Importance of Distribution and Quality: For best results, protein should be spread out throughout the day (e.g., 20-30g per meal), and sourced from a variety of high-quality foods.
Personalized Approach is Key: The right amount of protein depends on individual factors like weight, activity level, and health goals, not a one-size-fits-all number.

Your Personal Protein Blueprint

Understanding the impact of a 50-gram daily protein intake requires moving beyond a simple number. Your protein needs are not static; they are a dynamic calculation influenced by a variety of personal factors. This intake level supports the repair and maintenance of tissues, hormone production, and enzyme function. However, for someone who is physically active, attempting to build muscle, or over a certain age, 50 grams may fall short of providing optimal benefits and could lead to health issues.

The Adequacy of 50 Grams for Different Lifestyles

For the Sedentary Individual

If your lifestyle involves minimal physical activity, 50 grams of protein can be sufficient to meet the minimum RDA and maintain basic bodily functions. This intake helps prevent protein deficiency symptoms like fatigue, weakened immune function, and issues with hair, skin, and nails. However, even for this group, a higher protein intake may offer benefits like increased satiety and better body composition.

For the Active Individual or Athlete

For those who engage in regular exercise or resistance training, 50 grams is often inadequate. Intense physical activity requires higher protein intake for muscle repair and building new tissue. Active individuals may need significantly more protein, potentially double or triple the 50-gram mark. Insufficient protein can lead to stalled muscle growth, delayed recovery, loss of lean muscle mass, and persistent fatigue.

For Older Adults

Older adults often require a higher protein intake than younger, sedentary adults to help preserve muscle mass and strength due to age-related decline (sarcopenia). Sticking to just 50 grams could accelerate muscle loss and increase the risk of falls and frailty.

Potential Downsides of Insufficient Protein

Consuming too little protein over an extended period can have negative health consequences, as the body needs a consistent supply of amino acids for critical processes. Insufficient intake can cause the body to break down its own muscle tissue.

Symptoms of long-term inadequate protein intake include:

Loss of muscle mass
Weakened immune system
Fatigue and weakness
Skin, hair, and nail problems
Fluid retention (edema)
Increased appetite and cravings

The Role of Timing and Quality

Both the total amount and the timing and source of protein intake matter. Spreading protein evenly throughout the day can maximize synthesis and absorption. High-quality, complete proteins from sources like eggs, meat, and dairy provide all essential amino acids. Plant-based sources require variety for a complete profile.

How to Assess and Adjust Your Protein Intake

Assess your needs using a protein calculator based on your weight and activity level, then review your current diet. If your intake is low, incorporate more protein-rich foods throughout the day, such as eggs, Greek yogurt, fish, or plant-based options.

Protein Intake Comparison for a 160-pound Person


Lifestyle	Calculated Daily Protein Needs	Is 50g Adequate?	Potential Effects of 50g Intake
Sedentary	~58 grams (0.8g/kg)	Potentially, but on the low end.	Meets basic requirements, but misses potential benefits of higher intake.
Moderately Active	~80-100 grams (1.1-1.4g/kg)	No, likely too low.	Slower muscle recovery, potential muscle mass loss, increased fatigue.
Resistance Training	~116-160 grams (1.6-2.2g/kg)	No, significantly inadequate.	Impaired muscle growth, limited strength gains, prolonged soreness.

The Importance of a Balanced Approach

A healthy diet requires a balance of protein, carbohydrates, and healthy fats. Focusing only on protein at the expense of a varied diet can lead to other nutritional imbalances. Protein is one part of a larger nutritional picture.

For more information on protein recommendations, consult the American Heart Association's resource on protein.

Conclusion

For a truly sedentary person, 50 grams of protein daily may meet the basic recommended allowance and prevent deficiency. However, individual needs vary significantly. Active individuals, athletes, and older adults typically require more for muscle maintenance, growth, and optimal health. A personalized approach that considers your weight, activity level, and specific goals, along with a balanced diet, is key.

Frequently Asked Questions

No, for building muscle, 50 grams of protein a day is generally not enough. Active individuals and those doing resistance training need a much higher intake, often between 1.6 to 2.2 grams per kilogram of body weight, to support muscle repair and growth.

Yes, it is possible to lose weight on 50 grams of protein a day, but the outcome depends on your total calorie intake and activity level. For a sedentary person, this might be adequate, but for active people, it could lead to muscle loss instead of fat loss.

For a person with a low activity level, 50 grams of protein per day is often enough to meet the basic Recommended Dietary Allowance (RDA), supporting essential body functions and preventing protein deficiency.

Yes, if you have higher protein needs (due to activity or age), a daily intake of only 50 grams can lead to negative effects such as muscle loss, fatigue, poor recovery from exercise, and a weakened immune system.

It is not recommended to consume all your protein in one meal. Spreading your protein intake, such as aiming for 20-30 grams per meal, helps optimize protein synthesis and absorption for better muscle repair and satiety.

Signs you may not be getting enough protein include fatigue, hair thinning or brittle nails, constant hunger, slow-healing wounds, or a noticeable loss of muscle mass.

In healthy individuals, a protein intake of 50 grams a day is not considered harmful to the kidneys. Those with pre-existing kidney disease, however, should consult a doctor before making significant changes to their protein intake.

You can reach 50 grams of protein through a variety of sources. Examples include a combination of lean meats (chicken breast), eggs, Greek yogurt, fish like tuna, and plant-based options like tofu, legumes, and nuts.