Can You Build Muscle Without Protein?

Protein and muscle

It is physically impossible to build muscle without protein. In fact, without protein, you would die. There are essential amino acids that the body needs. They are classified as essential because the body cannot make them. If they are not taken in through the diet, the body cannot function properly, and a protein deficiency occurs and can lead to numerous health problems, including possible death.

We will break down the question further in this article to determine why protein is essential and how much protein is optimal to build muscle.

Why is protein essential to muscle growth?

Protein consists of 20 different amino acids. 9 out of these 20 amino acids cannot be made by the body and are thus called essential amino acids. These essential amino acids are why protein is necessary for muscle growth. The body cannot build skeletal muscle without a full complement of all amino acids, especially the essential ones.

Several essential amino acids play critical roles in the anabolic process, stimulating protein synthesis and ultimately lean mass increases. The most important essential amino acids are the BCAA or branched-chain amino acids, Leucine, Isoleucine and Valine. Please read our article about branched chain amino acids to learn how BCAA stimulates protein synthesis

Protein is by far the most anabolic of the macronutrients. That is not to say that carbohydrates and fat are unnecessary for muscle building, but the anabolic process grinds to a halt without protein. On the other hand, if you do not eat any carbohydrates, you can still build muscle.

Can you build muscle without protein?

Not eating enough protein makes it next to impossible for your body to build muscle. Without adequate protein, the body does not have enough amino acid building blocks to develop and construct protein and, ultimately, new muscle mass.

In fact, without protein, the body becomes catabolic. It begins to break down skeletal muscle to release vital amino acids needed to keep the crucial biological process functioning and preserve vital organs’ health and function. This environment is often found within the elderly population and leads to severe muscle wasting. Studies show that the most severe muscle loss in the elderly is in those who eat the lowest amounts of protein.[1]

Inadequate protein consumption puts the body in a protein deficit. Other things such as certain disease states can also put the body in a protein deficit. This deficit can lead to a protein deficiency, which can be very taxing and put pressure on the body as it tries to maintain homeostasis.

As mentioned above, the body will catabolize skeletal muscle to obtain amino acids to support protein synthesis in vital tissues and organs in the absence of protein.[2] This process is a survival mechanism left over from our hunter-gatherer days when food was hard to obtain and often scarce. If our ancestors did not eat for days or weeks, the body would catabolize skeletal muscle to get the amino acids it needed to keep the vital organs going to preserve life long enough for you to find food.

Image of bicep curl
Image of bicep curl

How much protein should you eat per day?

Athletes and bodybuilders should consume between 1.7 to 2.2 grams of protein per kilogram of body weight or 0.5 to 0.8 grams per pound of body weight per day. [3] This range is optimal to ensure that the body has enough amino acids to start and complete the anabolic process of creating and building muscle fibers. For sedentary individuals, the daily amounts they should consume are much less. Most governmental health agencies have recommended daily intake for protein of 0.8 grams per kilogram of body weight. This dosage works out to approximately :

  • 46 grams daily for sedentary women
  • 56 grams daily for sedentary men

As you can see, there is a big difference between the basic amount of protein that you need to survive and what you need to consume to build lean body mass. There is a lot of misinformation out in the world surrounding amino acid and protein requirements. Many doctors and dieticians are misinformed about muscle hypertrophy and wrongly state that a highly active athlete or bodybuilder does not need additional protein to build muscle. This line of thinking does not hold up in the real world and has been shown to be false by decades of bodybuilders showing that increased protein intake does lead to more significant gains in skeletal muscle. 

Another objection you might hear from dieticians and doctors about high protein intake is that it can damage the kidneys. This statement is not correct when talking about healthy people. Increased protein intake can further damage the kidneys if someone already has underlying renal impairment, but eating large amounts of protein will not cause any kidney damage if you have no underlying kidney problems.[4] Nutritionists at the Australian research organization CSIRO conducted a study that found test subjects on a low carbohydrate; high protein diet did not show any signs of renal impairment or damage after 1 year.[5]

In addition to the misconception that high protein intact hurts the kidneys, there are also several other myths surrounding high protein intake, such as it increases bone loss, heart disease and cancer risk. The data on high protein intake exacerbating or causing any of these conditions is unfounded in science. The research does not show that to be true.[6][7][8][9][10]

Protein is crucial for many body functions

In addition to being critical for muscle growth, protein and the amino acids within it play vital roles in many biological processes such as:

  • creation of immune system components
  • creation of plasma proteins
  • creation of peptide hormones
  • creation of intracellular and extracellular enzymes
  • creation of bone[11]


Hopefully, you better understand the crucial role of protein and its amino acids in the body and skeletal muscle. You should now know that you cannot build muscle without sufficient dietary protein intake. Your body cannot function optimally without healthy amounts of protein, and it is not a macronutrient you should avoid or restrict. 

Please also remember that high protein intake does not present the health risk that some in the nutrition world would lead you to believe, and in fact, it is the opposite, and it can help improve health and longevity.

Do not take the information contained within this article as health or medical advice. Please consult with your doctor for health or medical advice.


1Dietary protein adequacy and lower body versus whole body resistive training in older humans – Campbell – 2002 – The Journal of Physiology – Wiley Online Library
2The 2017 Sir David P Cuthbertson lecture. Amino acids and muscle protein metabolism in critical care – Clinical Nutrition (
3Indicator Amino Acid–Derived Estimate of Dietary Protein Requirement for Male Bodybuilders on a Nontraining Day Is Several-Fold Greater than the Current Recommended Dietary Allowance | The Journal of Nutrition | Oxford Academic (
4Changes in Kidney Function Do Not Differ between Healthy Adults Consuming Higher- Compared with Lower- or Normal-Protein Diets: A Systematic Review and Meta-Analysis | The Journal of Nutrition | Oxford Academic (
5Long-Term Effects of a Very Low Carbohydrate Compared With a… : Medicine (
6Dietary protein and bone health: a systematic review and meta-analysis from the National Osteoporosis Foundation | The American Journal of Clinical Nutrition | Oxford Academic (
7Dietary protein and bone health across the life-course: an updated systematic review and meta-analysis over 40 years | SpringerLink
8Plant Protein and Animal Proteins: Do They Differentially Affect Cardiovascular Disease Risk? | Advances in Nutrition | Oxford Academic (
9The association between dietary protein intake and colorectal cancer risk: a meta-analysis | World Journal of Surgical Oncology | Full Text (
10Nutrients | Free Full-Text | Dietary Protein Sources and Incidence of Breast Cancer: A Dose-Response Meta-Analysis of Prospective Studies (
11Low Protein Intake: The Impact on Calcium and Bone Homeostasis in Humans | The Journal of Nutrition | Oxford Academic (