How much protein should you eat a day?

November 1, 2025 •

4 min read

The recommended dietary allowance (RDA) for protein is 0.8 grams per kilogram of body weight, but this minimum might not be optimal for everyone. Your ideal daily intake depends on numerous factors, including your activity level, age, and personal health goals, so a blanket recommendation is often insufficient. Understanding these factors is key to determining how much protein should you eat a day to achieve your specific health and fitness objectives.

Quick Summary

This article explains how to calculate your personalized daily protein needs based on individual factors like activity level, age, and health goals. It also highlights the importance of protein for muscle repair, weight management, and overall health, while dispelling common myths.

Key Points

RDA is a minimum, not an optimal intake: The official 0.8g/kg figure is the bare minimum to prevent deficiency, but optimal intake is higher for most people, especially those who are active or older.
Calculate your needs based on activity and goals: Use a range of 1.2 to 2.0g per kg of body weight for active adults, with higher amounts for athletes and lower for sedentary individuals.
Higher protein aids weight loss: It increases satiety, boosts metabolism, and helps preserve lean muscle mass during a calorie deficit.
Spread protein throughout the day: Aim for 20–40g of protein per meal to maximize muscle protein synthesis and recovery.
Quality of protein matters: Prioritize complete protein sources like lean meats and dairy, or combine different plant sources to ensure you get all essential amino acids.
High protein is safe for healthy kidneys: The myth of kidney damage from high protein intake only applies to individuals with pre-existing kidney disease, not healthy adults.
Inadequate protein has negative effects: Insufficient protein can lead to muscle loss, a weakened immune system, and poor tissue repair.

Understanding Your Body's Protein Needs

Protein is a crucial macronutrient involved in virtually every cellular function, from building and repairing tissues to producing hormones and enzymes. While the baseline RDA serves as a general minimum, optimal protein intake is highly individual. For instance, an active athlete and a sedentary adult have vastly different needs. Athletes require more to support muscle repair and growth, while older adults may need a higher intake to combat age-related muscle loss, a condition known as sarcopenia.

The Baseline: The RDA for Sedentary Adults

For healthy, relatively inactive adults, the minimum Recommended Dietary Allowance (RDA) is 0.8 grams of protein per kilogram (or 0.36 grams per pound) of body weight. This is the amount needed to prevent a deficiency but is not necessarily the optimal amount for health and body composition goals. It's designed to cover basic nutritional requirements, not to maximize performance or muscle preservation.

Calculating Your Optimal Intake Based on Goals

To find a more personalized protein target, you need to consider your lifestyle and objectives. A more practical range for most healthy adults is between 1.2 and 2.0 grams of protein per kilogram of body weight.

Calculation examples:

A sedentary 70kg (154lb) individual: 70kg x 0.8g = 56 grams per day.
An active 70kg (154lb) individual: 70kg x 1.6g = 112 grams per day.
A 70kg (154lb) athlete aiming for muscle gain: 70kg x 2.0g = 140 grams per day.

Protein for Weight Loss and Muscle Maintenance

If you're trying to lose weight, a higher protein intake can be beneficial for several reasons. Protein is more satiating than carbohydrates or fat, which helps reduce hunger and calorie intake naturally. It also has a higher thermic effect, meaning your body burns more calories digesting it compared to other macronutrients. Most importantly, a higher protein intake helps preserve lean muscle mass during a calorie deficit, ensuring that the weight you lose is primarily fat.

For those focused on fat loss, studies suggest a range of 1.6 to 2.4 grams per kilogram of body weight is effective. Spreading protein intake across several meals is more effective than consuming it all in one sitting to maximize muscle protein synthesis.

Sources of Protein: Quality Over Quantity

Not all protein sources are created equal. High-quality proteins contain a full spectrum of essential amino acids, which are the building blocks your body needs. Animal products are considered complete proteins, but a thoughtful combination of plant-based foods can also provide all essential amino acids.

A comparison of common protein sources:


Food Source	Serving Size	Protein (g)	Type	Notes
Chicken Breast	3 oz (85g)	~25g	Complete	Very lean source of protein.
Salmon	3 oz (85g)	~22g	Complete	Rich in healthy omega-3 fatty acids.
Greek Yogurt	6 oz (170g)	~15-17g	Complete	Also provides calcium and probiotics.
Lentils	1 cup, cooked	~18g	Incomplete	Also high in fiber and iron.
Tofu	1/2 cup, firm	~20g	Complete	Versatile plant-based option.
Quinoa	1 cup, cooked	~8g	Complete	A gluten-free grain.
Whey Protein	1 scoop	~20-30g	Complete	Popular for post-workout recovery.

Optimal Protein Distribution

Beyond the total daily amount, distributing your protein intake evenly throughout the day is crucial, especially for active individuals. Aim for 20–40 grams of high-quality protein per meal to consistently stimulate muscle protein synthesis and recovery. For example, a 180-pound (82kg) individual aiming for 160g of protein could have four meals of 40g each.

Common Protein Myths Debunked

Myth: High protein intake damages healthy kidneys. The idea that too much protein harms the kidneys originated from studies on individuals with existing kidney issues. For healthy individuals, numerous studies show no negative impact on kidney function from higher protein diets.
Myth: You can only absorb a limited amount of protein per meal. Research indicates the body can utilize large amounts of protein, and any "excess" isn't wasted but rather digested and used over a longer period. What matters most is meeting your total daily requirement.
Myth: Plant proteins are inferior to animal proteins. While some individual plant sources may be incomplete, a varied vegan or vegetarian diet can easily provide all essential amino acids. The body combines amino acids from different foods throughout the day, so you don't need all essential aminos in a single meal.

The Dangers of Inadequate Protein Intake

Consistently eating too little protein can have serious health consequences. Over time, inadequate intake can lead to muscle loss (sarcopenia), a weakened immune system, poor wound healing, and brittle hair and nails. This is especially critical for older adults, whose protein needs increase due to reduced absorption and a higher risk of muscle wastage. The health benefits of sufficient protein are far-reaching and essential for long-term wellness.

Conclusion

There is no one-size-fits-all answer for how much protein should you eat a day, but a calculated approach based on your activity level and goals is the most effective strategy. Aiming for more than the sedentary RDA is often beneficial, especially for active individuals and those looking to manage their weight or preserve muscle as they age. By prioritizing a variety of high-quality protein sources and distributing your intake throughout the day, you can effectively fuel your body and support your long-term health and fitness goals. For personalized guidance, consult a registered dietitian.

Visit Examine.com for their comprehensive guide on optimal protein intake.

Frequently Asked Questions

For sedentary adults, the Recommended Dietary Allowance (RDA) is 0.8 grams of protein per kilogram of body weight, or about 0.36 grams per pound.

Athletes and individuals focused on muscle gain should aim for a higher intake, typically between 1.6 and 2.2 grams of protein per kilogram of body weight per day, combined with resistance training.

Yes, a high-protein diet can aid weight loss by increasing feelings of fullness, boosting your metabolism slightly, and helping to preserve lean muscle mass during a calorie deficit.

It is more effective to spread your protein intake throughout the day across multiple meals, aiming for 20-40 grams per meal. This strategy maximizes muscle protein synthesis more effectively than consuming a large amount in one sitting.

For healthy individuals, consuming up to 2.0 grams per kilogram of body weight is generally safe, and there is no evidence of kidney damage at these levels. Kidney strain is only a concern for those with pre-existing kidney disease.

Yes, plant-based diets can provide all essential amino acids. While some individual plant sources may be incomplete, a varied diet combining different plant proteins throughout the day will provide your body with all the amino acids it needs.

Older adults need a higher protein intake, often recommended at 1.0 to 1.2 grams per kilogram of body weight, to counteract age-related muscle loss and maintain overall health.

Insufficient protein intake can lead to muscle loss, a weakened immune system, poor wound healing, and impaired bodily functions over time, as protein is vital for countless processes.