If I Eat Too Much Protein Will My Kidneys Blow Up?

If you have healthy kidneys the answer looks to be a fairly resounding no [1-3].

It is important to note that even with all the noise on social media about this topic...

“Neither the Institute of Medicine nor the World Health Organization acknowledges that protein intake contributes to functional declines in renal function with age.” -Traylor et al. 2018 [4]

In order to understand this debate, we have to go through the rationale for why this ideology even exists in the first place.

Kidney function on a standard lab panel is primarily assessed by a value called Estimated Glomerular Filtration Rate or eGFR. The keyword there is estimated. There are multiple equations that do this, but the primary equations are the CKD-EPI Creatinine (2009) and MDRD equation - these methods pretty much just use serum creatinine and age.

This is a huge problem for athletes because serum creatinine directly correlates with muscle mass, which means that as you build more muscle your serum creatinine will likely increase, as muscle mass accounts for as much as 98% of your creatine stores [5-7].

Hold up, so more muscle is a bad thing?

For the average American, absolutely not.