Why Are Protein Recommendations So High?

November 3, 2025 •

3 min read

The Recommended Dietary Allowance (RDA) for protein is 0.8 grams per kilogram of body weight, yet many health and fitness experts now suggest significantly higher intakes for optimal health. This raises the question: why are protein recommendations so high, particularly when the RDA appears quite low?

Quick Summary

This guide explains the key factors driving higher protein intake recommendations, moving beyond the minimums needed to prevent deficiency. It covers increased needs for muscle repair and growth, satiety for weight management, and combating age-related muscle loss.

Key Points

RDA is a Minimum, not an Optimum: The official RDA of 0.8g/kg is designed to prevent deficiency, not to support optimal muscle mass, strength, or metabolic health.
Athletes Require More Protein: Higher protein intake, typically 1.2-2.2+ g/kg, is necessary for active individuals to repair muscle tissue and promote growth following exercise.
Protein Boosts Satiety and Metabolism: Higher protein intake can increase feelings of fullness, reduce hunger hormones, and slightly boost calorie burn through the thermic effect of food.
Older Adults Need Higher Protein: Age-related muscle loss (sarcopenia) and anabolic resistance in older adults necessitate a higher protein intake (1.0-1.2+ g/kg) to maintain muscle and function.
Protein Quality and Timing Matter: Spreading protein intake throughout the day with high-quality, complete protein sources (rich in leucine) is most effective for muscle protein synthesis.
Higher Intake Protects Muscle During Weight Loss: For those in a calorie deficit, a higher protein diet helps preserve lean body mass, ensuring weight loss comes primarily from fat.

The Flaws of the Standard RDA

The Recommended Dietary Allowance (RDA) of 0.8 grams of protein per kilogram of body weight is the minimum requirement for sedentary adults to prevent deficiency. However, this amount isn't considered optimal for overall health, muscle maintenance, or achieving specific fitness goals. This distinction between minimum and optimal intake helps explain why protein recommendations so high today.

Increased Needs for Active Lifestyles

Individuals who are physically active, whether through endurance activities or strength training, require more protein than the standard RDA. Exercise causes minor damage to muscle fibers, and protein is crucial for their repair and growth. Without sufficient protein, recovery is slowed, and muscle development is limited. Athletes may need between 1.2 and 2.2 grams per kilogram of body weight, or even more, depending on their training intensity and frequency. This higher intake ensures a consistent supply of amino acids for muscle protein synthesis.

Protein's Role in Weight Management

Protein is also important for weight loss and managing body composition. A higher protein intake can increase feelings of fullness and reduce hunger, which aids in following a calorie-restricted diet. Protein requires more energy to digest than carbohydrates or fats, a process known as the thermic effect of food (TEF). Additionally, adequate protein helps maintain lean muscle mass during weight loss, preventing the body from breaking down muscle for energy.

Combating Age-Related Muscle Loss

Aging is often accompanied by a decline in muscle mass and function, known as sarcopenia. Older adults also experience anabolic resistance, meaning they need more protein to stimulate muscle protein synthesis effectively. Consequently, recommendations for older adults are typically higher than the standard RDA, often ranging from 1.0 to 1.2 grams per kilogram of body weight, to help preserve muscle mass and strength. Combining higher protein intake with resistance training can improve physical performance and reduce the risk of frailty.

The Quality of Your Protein Source Matters

The effectiveness of a protein source depends on its amino acid composition and how well it is digested. Complete proteins provide all nine essential amino acids necessary for muscle building. Animal products like meat, fish, eggs, and dairy are complete proteins, rich in leucine which is key for muscle protein synthesis. Plant-based proteins need to be combined to ensure a complete amino acid profile, so variety is important for vegetarians and vegans.

Comparing Standard RDA to Optimal Intake

To highlight the difference between the minimum recommendation and optimal intake, consider a 70kg (154 lb) individual. The standard RDA is a baseline, while optimal intake addresses specific health goals.


Factor	Standard RDA (for sedentary adult)	Optimal Intake (for specific goals)
Total Daily Protein	56 grams (0.8g/kg)	84-154+ grams (1.2-2.2+g/kg)
Primary Goal	Prevent deficiency, meet basic needs	Maximize muscle growth, aid recovery, manage weight, combat aging
Effect on Muscle	Sufficient for maintenance, not for growth	Promotes repair, synthesis, and hypertrophy
Impact on Satiety	Minor effect	Significant increase in fullness
Thermic Effect	Standard digestion	Elevated caloric expenditure during digestion
Best For	Completely inactive individuals	Athletes, active people, those seeking weight loss, seniors

Conclusion

While the basic RDA for protein prevents deficiency, it is not optimized for those with specific health and fitness goals. Higher protein recommendations are driven by protein's vital roles in muscle building, weight management, and maintaining health as we age. For those aiming to enhance their physical health, a protein intake exceeding the baseline RDA, customized to individual needs, is often recommended. Always consult a healthcare professional or registered dietitian to determine the appropriate intake for your body and goals.

A Note on Authoritative Sources

For further information, reputable sources like the Harvard T.H. Chan School of Public Health and the National Institutes of Health offer valuable insights into protein and nutrition. The Harvard Health article on daily protein needs is a particularly helpful resource: https://www.health.harvard.edu/blog/how-much-protein-do-you-need-every-day-201506188096.

Frequently Asked Questions

The RDA for protein is 0.8 grams per kilogram of body weight for healthy, sedentary adults.

The RDA is the minimum required to prevent deficiency, not the optimal amount for maximizing muscle growth, supporting active lifestyles, or benefiting older adults.

Athletes and active people typically need between 1.2 and 2.2 grams of protein per kilogram of body weight per day to support muscle repair and growth.

Yes, a higher protein intake promotes weight loss by increasing satiety, boosting metabolism, and helping to preserve lean muscle mass during a calorie deficit.

As people age, they become less sensitive to protein's muscle-building effects (anabolic resistance), so a higher intake of 1.0 to 1.2 grams per kilogram of body weight is often recommended to combat muscle loss.

Both can be effective. Animal sources are complete proteins with all essential amino acids. Plant-based diets need a variety of sources to ensure a full spectrum of amino acids, though supplements can also be used.

While it's difficult for most healthy individuals to consume a harmful amount, consistently very high protein intakes can strain the kidneys, especially in people with pre-existing kidney disease. The excess is simply not used effectively by the body.