Why do kidney patients take or need protein supplements?

Protein supplements are needed only when patients are on a low- or very low-protein diet. Low- or very low-protein diets are not safe over the long term without ensuring daily protein intake needs are met.  If you are on a low- or very low-protein diet long enough, protein malnutrition will become an issue unless protein supplementation is added.

Protein needs are met by supplying the eight essential amino acids your body cannot make on its own.  The essential amino acids must come from dietary intake.

List of essential amino acids

  • Histidine,
  • Isoleucine,
  • Leucine,
  • Lysine, 
  • Methionine, 
  • Phenylalanine, 
  • Threonine, 
  • Tryptophan,
  • Valine.  

The non-essential amino acid tyrosine may be added to some formulations.  Some research suggests that tyrosine production is impaired in end-stage renal disease or stage 5. Tyrosine is not needed for stage 3 patients and may or may not be needed for stage 4 patients. 

Keto Analogues, also called keto analogs or keto acids, are the same essential amino acids with the nitrogen component removed.  The benefit of keto analogues is lower nitrogen intake while ensuring you are getting the recommended daily amounts of essential amino acids.  This also happens naturally in your body when dietary protein is consumed. Your body breaks down the protein in the component parts (amino acids) and then removes the nitrogen which is filtered out by your kidneys.  You see nitrogen waste products as blood urea nitrogen or BUN on your blood tests. 

This is not possible for some amino acids, but is commonly done for leucine, isoleucine, methionine, valine, and phenylalanine.  In some cases, tryptophan and tyrosine can also be converted to keto analogues, as well.

Keto analogues provide the same nutrition as amino acids, but dramatically reduce the amount of protein waste products your kidneys have to filter.

Nitrogen content is roughly equal for protein content for our purposes.  Higher protein foods have a higher nitrogen content.

What forms do protein supplements for kidney patients come in?

100% Amino acids 

A blend of keto analogue and amino acids

Both come in pill or powder forms.

In order to make a great decision for our health, we need to know what to look for when reading the labels and what issues impact our health.   

  • What does the research say about this issue?
  • How strong is the research?
  • Is this important enough to worry about?
  • Is a product safe for us to take?

And so on.

Again, the best defense against old data and marketing hype are current facts based on 2020 data and not on research that is 50 years old.