

Optimal Protein Intake For Muscle Growth (Science-Based)

Connor Sellers
Published by Connor Sellers
Fact checked by Donald Christman, BHSc FACT CHECKED
Last updated: March 8, 2022

Contrary to popular opinion, consuming more proteins than you need can cause constipation or worsen kidney issues.

You must consume the right amount of protein to build muscle. But with different sources, tips, and calculations, people are confused about how much protein they need.

I spent weeks reading various published journals and clinical studies and consulted a certified dietitian on adequate protein intake to build muscle.

In this article, I will share how to calculate your body's protein needs and get enough protein.

Summary of Article

  • Proteins are our body's building blocks that are crucial for losing weight and building lean body mass.
  • The exact protein you need to build muscle depends on many factors, and recommendations vary from study to study.
  • You can get adequate amounts from whey protein, lean meats, dairy products, and plant-based sources.

What Is Protein And Why Is It Important?

different protein food sources

Proteins are macronutrients and the main building blocks of our body. They’re made up of amino acids linked together, forming long-chain proteins that fold into a complex shape.

The amino acids that make up a protein determine its role in the body. Proteins are commonly known for repairing body tissues and building muscle mass, but they provide more than that.

Here are some of its functions:

  • Provides more energy [1].
  • Allow chemical reactions to take place (e.g., digestive enzymes) [2].
  • Send messages in the body (e.g., hormones like insulin) [3].
  • Provide structure (e.g., keratin, collagen, and elastin) [4,5].

Now, here's how they help you achieve your body composition goals.

Aids in Losing Weight

woman with a tape measure on her body

Consuming protein can help you lose weight because it helps suppress appetite and boost your metabolic rate.

In one study, subjects were exposed to different diets: 

  • A diet rich in protein
  • High-fat diet
  • A diet high in carbohydrates

It turned out that men felt less hungry with a high protein diet than the other two diets [6].

Evidence shows that protein intake can help you feel full by reducing the levels of hunger hormone Ghrelin in our body and increasing levels of peptide YY [7,8].

In short, consuming protein can help you eat less without intentionally limiting yourself and thus prevent you from overeating.

It has also been shown to increase energy consumption, which leads to higher calorie burning [9].

One study shows that increasing daily protein intake for about 15% to 18% helps reduce the number of weight people regain by 50% [10].

Encourages Muscle Growth

Consuming proteins and muscle growth go hand in hand. Our bodies use amino acids for muscle protein synthesis (MPS), the process of creating proteins to repair muscle damage caused by intense exercise.

Intense exercise can cause micro-tears in the muscles, leading to a muscle protein breakdown (MPB), a process opposite to muscle protein synthesis where proteins are lost.

Amino acids coming from proteins will be transported to your muscles to repair the damaged cells and create new muscle tissue.

"Those who are new to exercise have a unique ability to lose body fat while also building muscle. However, for those who are advanced or looking to gain muscle mass as quickly as possible, eating more calories than you burn in any given day will be important for a while during your muscle-building phase."— Tara Allen, Registered Nurse and Certified Health Coach, Nutrition Coach, and Personal Trainer

But, repairing damaged muscle tissues doesn’t automatically lead to muscle growth.

To build muscle, the rate of creating more protein (MPS) has to outpace the rate of losing protein (MBP) (also called nitrogen balance). If the opposite happens—MBP outpaces MPS, muscle loss occurs.

This makes higher protein intake crucial for building lean body mass.

However, note the muscle-building equation also includes resistance training, adequate rest, and sometimes increased total calories for weight gain.

How to Get Enough Protein?

set of food and white powder

Getting adequate protein for increasing muscle mass is crucial, but so is the quality of your protein sources. So, here are the best sources of protein to include in your meals.

High-Protein Foods

Foods high in protein include:

  • Lean meat, fish, eggs, whey protein, and dairy products have all the essential amino acids (amino acids that your body can't make), and so they are called high-quality or complete protein.
  • Quinoa, soy products, and the seed of a leafy green known as amaranth (famous in Asia and the Mediterranean) are also high in protein.
  • Plant sources like beans, lentils, nuts, and whole grains are considered 'incomplete' because they lack essential amino acids.

If you are currently on a plant-based diet, you can still get adequate protein by eating a variety of food sources. For example, a meal with cereals and legumes provides you with the essential amino acids found in a usual meat dish.

Protein Powder

If meeting your protein requirements with food is a struggle, protein powder comes in handy.

Athletes and bodybuilders often use protein powders as intensive physical activities require higher levels of protein.

Protein powder often comes from food sources like soy that has complete protein. Having a protein shake helps increase muscle mass and speed up the recovery process.

Calculate Your Protein Needs for Muscle Building

workout needs

An active individual needs to eat or consume more protein than an average person. The minimum amount needed to gain muscle depends on age, fitness level, and physical activities, but exactly how much protein each person needs remains debatable.

One study shows that a person needs a minimum of 1.6-1.7 grams of protein per kilogram of body weight (0.7-0.8 grams of protein per pound) to maintain lean mass with strength training [11].

While another recent study suggests taking as high as 1.8-2.0 grams of protein per kilogram of body weight (0.8-0.9 grams for every pound of body weight) is beneficial [12].

However, a review of 49 studies found that protein consumption of more than 1.6 grams per kilogram of body weight (or 0.72 grams for every pound) is not beneficial for those trying to gain muscle [13].

While there is no definitive answer, the American College of Sports Medicine's suggested protein intake seems reasonable if we use these science-based recommendations.

The American College of Sports Medicine (ACSM) says a person who lifts weights regularly or trains for running or cycling events needs 1.2-1.7 grams of protein for each kilogram of body weight (0.5-0.8 grams per pound) every day to build muscle mass combining physical activity [14].

What Happens When You Eat Too Much Protein?

women in pain

Eating protein in high amounts is considered safe for healthy individuals, but it doesn't necessarily mean better for your well-being.

There can be minor side effects of having a high protein consumption, such as: 

However, note that these minor side effects are usually caused by a high-protein meal that restricts other macros, like healthy fats and carbs.

Furthermore, consuming protein mainly from red meat can lead to risks of heart disease because they contain high amounts of saturated fat [15].

Some reports say too much protein may cause kidney problems because it increases the workload of the kidneys.

But, studies show that high protein is safe for healthy adults and can only negatively affect those with decreased kidney function [16].


Is 100 Grams of Protein Enough to Build Muscle?

An active person must aim for a protein intake of 1.2-1.7 grams per kilogram of body weight (that's 0.5-0.8 grams for every pound) daily for muscle growth, says the American College of Sports Medicine. So, on average, a 75-kilogram individual should aim for 75g-128g of protein daily.

How Much Protein Should I Be Eating to Lose Weight?

Dietary guidelines suggest that you should be eating 46–56 g or 0.8 grams of protein per kilogram of ideal body weight (optimal weight based on your height, gender, and age) daily to lose weight [17].

How Much Is Needed After a Workout?

Evidence suggests it is beneficial to consume at least 0.3-0.5 g per kilogram (or 0.14-0.23 grams per pound) of body weight after a strenuous workout [18].

How Much Protein Helps Build Muscle?

The bottom line is that protein is vital for several functions in the body that include:

  • Providing structure and support
  • Building and repairing tissues
  • Forming hormones and enzymes.

When it comes to our body composition goals, it helps us lose weight and build more muscle.

Protein requirements for each person remain a debate. But, following the suggested daily protein intake of 1.2-1.7 grams of protein per kilogram (or 0.5-0.8 grams per pound) of body weight is scientifically proven to help muscle gain.

You can get your protein needs from high-quality animal-based and plant-based protein and protein powders. But, consuming high protein is just one of the other factors needed for building muscle.

It's a combination of regular strength training, adequate rest, and an increased overall calorie intake that aids muscle gain.



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