What is the recommended RDA for protein and why it's just the minimum

November 2, 2025 •

4 min read

The Recommended Dietary Allowance (RDA) for protein for adults is 0.8 grams per kilogram of body weight, a number that has remained relatively unchanged for decades. However, this figure represents the minimum requirement to prevent deficiency, not the optimal intake for good health, muscle maintenance, or performance, which can vary significantly depending on individual factors.

Quick Summary

The protein RDA is a baseline minimum, with individual needs fluctuating based on age, activity level, and health goals. Optimal intake for muscle growth, strength, and age-related prevention is often higher, ranging from 1.2 to 2.0+ g/kg per day.

Key Points

RDA is a Minimum: The official RDA of 0.8 g/kg for protein is the minimum required to prevent deficiency in sedentary adults, not the optimal amount for health or performance.
Age Increases Needs: Older adults (over 50) face anabolic resistance and often require 1.0–1.2 g/kg/d or more to effectively stimulate muscle protein synthesis and prevent muscle loss.
Activity Boosts Demand: Athletes and physically active individuals should target a higher protein intake, typically ranging from 1.4–2.0 g/kg/d, to support muscle repair and growth.
Quality and Timing Matter: Focusing on high-quality protein sources, whether animal or varied plant-based, and distributing intake evenly throughout the day can maximize muscle benefits.
Context is Crucial: Your ideal protein intake is highly personalized and depends on your age, activity level, and specific goals, requiring a more nuanced approach than simply following the baseline RDA.

Understanding the Standard Protein RDA

For decades, the Recommended Dietary Allowance (RDA) for protein has been set at 0.8 grams per kilogram of body weight per day (g/kg/d) for adults aged 18 and over. This figure, derived primarily from nitrogen balance studies conducted on healthy young men, represents the minimal amount of protein needed to prevent a negative nitrogen balance and avert outright deficiency.

It's crucial to understand that the RDA is not an optimal or maximal target for everyone. It serves as a floor, a basic requirement for general health in a sedentary population. Factors such as a person's age, physical activity level, and specific health goals can dramatically increase their optimal protein needs beyond this baseline.

Protein Requirements for Different Life Stages

Protein requirements are not static throughout life. They change based on growth, metabolism, and the body's natural processes. Let's look at how needs evolve with age.

Older Adults: Combating Anabolic Resistance

As we age, our bodies become less efficient at utilizing dietary protein to build muscle, a phenomenon known as anabolic resistance. This means older adults need a higher protein intake per meal to stimulate muscle protein synthesis effectively. Many expert groups now recommend a daily intake of 1.0–1.2 g/kg/d or even higher for healthy individuals over 65, with needs increasing further during illness or injury.

Increased protein intake, especially when combined with resistance exercise, can significantly help in mitigating age-related muscle loss (sarcopenia) and improving overall physical function.

Athletes and Active Individuals

For anyone engaged in regular physical activity, from endurance sports to strength training, protein needs are elevated to support muscle repair, recovery, and growth. The International Society of Sports Nutrition recommends a protein intake of 1.4–2.0 g/kg/d for active individuals.

Endurance Athletes: A lower-end range of 1.2–1.6 g/kg/d is often sufficient to support recovery.
Strength/Power Athletes: A higher intake, up to 2.0 g/kg/d, is more beneficial for maximizing muscle mass gains.
Calorie Restriction: During periods of weight loss or calorie restriction, protein needs increase further (1.8–2.7 g/kg/d) to help preserve lean body mass while shedding fat.

Pregnancy and Lactation

During pregnancy, a woman's body requires extra protein to support fetal tissue development, the placenta, breasts, and an increase in blood supply. The RDA increases during the second and third trimesters. Similarly, breastfeeding requires higher protein intake to produce breast milk.

The Role of Protein Quality and Timing

Not all protein is created equal. The quality of a protein source is determined by its amino acid profile and digestibility. Complete proteins, typically from animal sources like meat, dairy, and eggs, contain all nine essential amino acids the body cannot produce on its own. Many plant-based proteins are incomplete, meaning they lack sufficient amounts of one or more essential amino acids. However, a varied diet of plant proteins can easily provide all essential amino acids throughout the day.

Studies also suggest that distributing protein intake evenly throughout the day, particularly ensuring an adequate amount (around 20–40g) at each meal, can maximize muscle protein synthesis. This even distribution is often more beneficial than consuming most of your protein in one large meal.

Animal vs. Plant Protein

For a balanced and healthy diet, many choose a combination of animal and plant proteins. Plant-based proteins often come with added benefits like fiber and phytochemicals, while animal proteins are generally more complete and easier to absorb.


Feature	Animal Protein	Plant Protein
Completeness	Most sources are complete proteins, containing all nine essential amino acids.	Most sources are incomplete, requiring variety for a complete profile.
Digestibility	Generally highly digestible and easily absorbed by the body.	Can vary; fiber and antinutrients may slightly lower digestibility.
Other Nutrients	Rich in vitamin B12, iron, and zinc.	Rich in fiber, antioxidants, and phytochemicals.
Saturated Fat	Some sources (e.g., red meat) can be high in saturated fat.	Typically low in saturated fat and may contain healthy unsaturated fats.
Common Sources	Meat, poultry, fish, eggs, dairy.	Legumes, nuts, seeds, soy products, whole grains.

Customizing Your Protein Intake

Calculating your optimal protein intake involves considering your individual circumstances. While the basic 0.8 g/kg RDA is a starting point, it's not the ceiling. Active individuals, older adults, and those with specific body composition goals often benefit from higher intakes, up to 1.2–2.0+ g/kg per day.

To apply these recommendations effectively, a personalized approach is key. A consultation with a registered dietitian can help create a plan that accounts for your specific health status, dietary preferences, and fitness goals. By focusing on high-quality protein sources and distributing your intake strategically throughout the day, you can move beyond the minimum RDA and optimize your diet for better health and performance.

Conclusion: Beyond the Minimum

Ultimately, understanding what is the recommended RDA for protein is only the first step. For most people, particularly those who are active or over the age of 50, aiming for a protein intake significantly higher than the standard 0.8 g/kg recommendation is beneficial. By focusing on a diverse range of high-quality protein sources, distributing them effectively across meals, and combining them with exercise, you can better support muscle health, recovery, and long-term well-being. The RDA provides a safety net against deficiency, but achieving optimal health often requires reaching for higher protein targets tailored to your life stage and lifestyle. Source: Journal of the American Medical Directors Association

Frequently Asked Questions

To get a baseline, multiply your body weight in kilograms by 0.8. However, for a more accurate target, consider your activity level. Active individuals should aim for 1.4–2.0 g/kg, and older adults should target 1.0–1.2 g/kg.

For healthy individuals, consuming a higher protein diet within the recommended range (up to 35% of total calories) is generally considered safe. However, excessive long-term intake (>2.0 g/kg/d) can potentially strain the kidneys in some individuals, and it should be managed under medical advice, especially for those with pre-existing kidney conditions.

Yes, it is entirely possible to meet your protein needs on a plant-based diet. While many plant proteins are 'incomplete' on their own, consuming a variety of plant sources throughout the day, such as legumes, grains, nuts, and seeds, ensures you get all the essential amino acids.

Excellent protein sources include lean meats, fish, eggs, dairy products (like Greek yogurt and cottage cheese), soy, legumes (beans, lentils), nuts, and seeds. Varying your sources ensures a complete amino acid profile.

Older adults need more protein primarily due to 'anabolic resistance,' a reduced sensitivity of muscles to dietary protein. A higher intake is necessary to adequately stimulate muscle protein synthesis and counteract age-related muscle loss.

For optimal muscle protein synthesis, aim to distribute your protein intake evenly across all meals, rather than consuming most of it in one sitting. Targeting 20–40 grams per meal is a practical approach for active individuals.

While it's important to get enough protein overall, consuming 15–25 grams of high-quality protein within two hours after a workout is recommended to help repair and rebuild muscle tissue.