What's the minimum protein intake to not lose muscle?

December 20, 2025 •

4 min read

While the standard recommended dietary allowance (RDA) for protein is 0.8 grams per kilogram of body weight, this minimum may not be sufficient to prevent muscle loss, especially for active individuals and older adults. Optimal intake varies significantly depending on several key factors.

Quick Summary

Determining the right daily protein intake to prevent muscle loss depends on individual factors like age, physical activity, and body composition. The standard RDA is often too low for effective muscle preservation. A higher, more personalized intake is typically required to maintain or build muscle mass effectively.

Key Points

RDA is Insufficient: The official RDA of 0.8 g/kg is the bare minimum to prevent deficiency, not to prevent muscle loss, particularly in active or older populations.
Active People Need More: Individuals who exercise regularly, especially with resistance training, require 1.2 to 2.0 grams of protein per kilogram of body weight to preserve and build muscle.
Age Increases Demand: As we get older, our bodies become less efficient at utilizing protein, necessitating a higher intake of 1.2 to 1.6 g/kg to combat age-related muscle loss (sarcopenia).
Spread Out Intake: Distributing protein evenly throughout the day, aiming for 25-30 grams per meal, is more effective for sustaining muscle protein synthesis than consuming a large amount in one sitting.
Factor in Body Weight and Goals: The optimal protein intake for preventing muscle loss varies based on individual factors like current weight, goal weight (if applicable), and level of physical activity.

Understanding Standard Protein Recommendations

For years, the Recommended Dietary Allowance (RDA) for protein has been set at 0.8 grams per kilogram of body weight for the average sedentary adult. However, this figure is primarily designed to prevent a deficiency, not to optimize body composition or prevent muscle atrophy. Muscle mass is in a constant state of flux, with protein synthesis and breakdown occurring continuously. To prevent a net loss of muscle, protein synthesis must equal or exceed breakdown. For many individuals, especially those with an active lifestyle or who are aging, a higher intake is necessary to tip the scales in favor of muscle maintenance.

Protein Needs by Demographics and Goals

Protein requirements are not one-size-fits-all. A healthy, active adult will have different needs than a sedentary older adult or someone on a weight loss journey. Factors like age, activity level, and body weight all play a crucial role in determining the ideal intake to prevent muscle loss.

Minimums for Sedentary Individuals

Even those with a largely sedentary lifestyle may benefit from consuming more protein than the 0.8 g/kg RDA. Some experts suggest that a minimum of 1.2 g/kg per day is a more appropriate starting point to support overall health and prevent age-related muscle decline. In a study that overfed sedentary individuals, the group on a low-protein diet (0.7 g/kg) actually lost some lean body mass, while the higher-protein groups gained it.

Increased Demands for Active Lifestyles

Physical activity significantly increases protein requirements. When you exercise, especially resistance training, you create microscopic tears in muscle fibers that need to be repaired. Protein provides the amino acids necessary for this repair, leading to stronger muscle. Athletes and physically active people need between 1.2 and 2.0 grams of protein per kilogram of body weight per day. This range depends on the intensity and frequency of the exercise. For those engaging in consistent resistance training, the upper end of this spectrum is often necessary to maximize muscle repair and prevent loss.

Preserving Muscle During Weight Loss

When in a caloric deficit to lose weight, the body is at a higher risk of losing muscle mass along with fat. Consuming a high-protein diet is a powerful strategy to preserve lean body mass during this period. Recommendations for weight loss often range from 1.6 to 2.4 grams per kilogram of body weight. A higher protein intake promotes satiety, helping to manage hunger on a lower-calorie diet, and also slightly increases the thermic effect of food.

The Impact of Age on Protein Requirements

As we age, our bodies become less efficient at using protein to build muscle, a phenomenon known as anabolic resistance. This, coupled with the natural decline in muscle mass called sarcopenia, means that older adults need to be more proactive about their protein intake. For adults over 65, experts recommend a higher intake of 1.2 to 1.6 grams per kilogram of body weight daily to help counteract muscle loss and maintain physical function. For older adults who are sick, injured, or inactive, protein needs can increase even further, sometimes requiring 1.6 g/kg or more.

The Role of Protein Quality and Timing

Protein quality, based on its amino acid profile, is also a key consideration. Complete proteins contain all nine essential amino acids. Animal-based sources are typically complete, while many plant-based proteins are not. Those following a plant-based diet should combine different protein sources throughout the day to ensure a complete amino acid profile. While animal protein sources are often cited for their higher leucine content, adequate total intake can overcome the differences.

The importance of protein timing has been debated, but most experts agree that spreading protein intake evenly throughout the day is more effective for muscle maintenance than trying to hit a narrow 'anabolic window' post-workout. Consuming 25-30 grams of high-quality protein at each meal is a good strategy to maximize muscle protein synthesis. Some studies also suggest a higher protein intake at breakfast could be beneficial. A food-first approach, prioritizing protein from whole foods, is recommended over relying solely on supplements.

Comparison of Protein Intake Recommendations


Demographic	Recommended Protein (g/kg/day)	Notes
Sedentary Adults	1.2+	Above the RDA to prevent long-term muscle loss
Older Adults (>65)	1.2–1.6	To combat anabolic resistance and sarcopenia
Active Individuals	1.2–2.0	Dependent on intensity and frequency of exercise
Weight Loss (Preserving Muscle)	1.6–2.4	Higher intake helps preserve lean mass during a calorie deficit
Plant-Based Athletes	1.6–2.2	Focus on combining various plant sources

Practical Steps to Meet Your Protein Needs

Calculate Your Target: Multiply your body weight in kilograms by the recommended factor for your demographic. (e.g., 75 kg active person x 1.6 g/kg = 120 grams). If overweight, some suggest using your goal weight.
Prioritize a "Food-First" Approach: Integrate lean meats, eggs, dairy, fish, and legumes into your meals and snacks.
Plan Your Day: Distribute your target protein intake across three to four meals and snacks to fuel your muscles consistently.
Consider Supplements Wisely: Protein powders can be a convenient way to meet higher protein goals, especially for busy individuals.

Conclusion: Optimizing for Preservation

Determining what's the minimum protein intake to not lose muscle depends on a nuanced understanding of your personal physiology and lifestyle. The standard 0.8 g/kg RDA should be considered a baseline to prevent deficiency, not a target for optimal muscle health. Most people, especially those who are active or aging, will need significantly more to preserve lean body mass. By calculating your personalized needs, focusing on high-quality sources, and spreading your intake throughout the day, you can effectively maintain muscle mass and support your overall health and fitness goals. For the most accurate and personalized advice, consider consulting a registered dietitian who can take your unique health profile into account.

High-Quality Protein Sources

Animal-Based: Chicken breast, lean beef, salmon, eggs, Greek yogurt, and cottage cheese.
Plant-Based: Tofu, tempeh, lentils, chickpeas, edamame, and various nuts and seeds.
Supplements: Whey, casein, and blended plant-based protein powders.

Frequently Asked Questions

For many people, especially active or older individuals, the 0.8 g/kg RDA is insufficient to prevent muscle loss. This value is a baseline to prevent deficiency, not to optimize body composition. Higher protein intake is often needed for effective muscle preservation.

Multiply your weight in kilograms by the appropriate factor for your activity level and age. For example, a sedentary person might aim for 1.2 g/kg, while an active person might aim for 1.6 g/kg. If you are overweight, some experts recommend using your goal weight for calculation.

While the impact of a strict post-workout 'anabolic window' is debated, most evidence suggests that spreading your total daily protein intake evenly across meals and snacks is more important for consistent muscle repair and maintenance. Consuming protein at each meal is a good strategy.

Yes, due to anabolic resistance, older adults require a higher protein intake, typically 1.2 to 1.6 g/kg per day, to maintain muscle mass and combat age-related muscle loss, or sarcopenia.

Yes, it is possible to prevent muscle loss on a plant-based diet, but it requires careful planning. Combining various plant-based protein sources ensures you get a complete profile of essential amino acids. Aim for the higher end of protein recommendations for your activity level.

Failing to meet minimum protein needs can lead to a state of net muscle protein breakdown, resulting in a gradual loss of muscle mass over time. This can negatively impact strength, metabolism, and overall physical function.

While it's ideal to meet your protein needs through whole foods, supplements like protein powders can be a convenient and effective way to ensure adequate intake, especially for those with high protein requirements or busy schedules. It is best used as a supplement to, not a replacement for, whole foods.