The media is reporting that a high protein diet will damage your kidneys. Let’s look into this.

Does Protein Cause Kidney Damage?

Written by Russ Howe PTI, and most recently updated 1 day ago.

7 min read

The media have reported that eating a high protein diet can cause kidney damage, and athletes all over the world are misplacing their excrement.

I’m going to be looking into these claims today, to determine whether this is something you should be concerned about, or whether it’s another case of the media being absolute thundercunts.

Table of Contents

does protein damage kidneys

The belief that protein causes kidney damage dates all the way back to the 1970s.

One of the main jobs of the kidneys is to break down the protein that you eat, so it’s long been theorized that consuming a diet which is much higher in protein (e.g. athletes and bodybuilders who are trying to build muscle) may cause an overload which the kidneys could not deal with.

Concerns deepened in 1988, when a study from Berlin, Germany, claimed to have found a direct link between high protein diets and kidney problems. The researchers said that participants who ate more protein had a bigger glomerular filtration rate. I realize that probably makes zero sense to the casual gymgoer, but basically GFR is used as a marker to measure waste filtration levels in the kidneys, so the researchers believed that increasing GFR showed that eating more protein did indeed cause more stress. (1)

More research was needed at this stage, but it did not arrive until 2003.

The ’03 study came from researchers at Harvard Medical School, and it showed us two very interesting things. The first is that the body is perfectly capable of handling the additional requirements created by eating protein (stating that “it’s literally the kidney’s job description to do this”), and the second is that participants who had pre-existing kidney issues (e.g. urea cycle disorder) did experience some problems. (2)

So basically unless you have pre-existing kidney damage, you’re good to go.

These findings have since been re-confirmed in several follow-up studies, and perhaps the most interesting of those came from The University of Brussels, where researchers took a direct look at the effects of a bodybuilding-style high protein diet on the kidneys of bodybuilders and athletes.

They had participants eating a whopping 1.3 grams of protein per lb of body weight, which is significantly higher than the dose used in most studies on high protein intake (anything above 0.7 is generally considered high), and the results confirmed there were no negative effects. (3)

That should lay any fears you may have had to rest, but I can go one better here…

In 2016 a team of researchers from Nova Southeastern University published a comprehensive 12-month study on this topic (the longest by far), in which they had participants eating 1.1 grams of protein per lb during the first six months of the trial, and then a massive 1.5 grams of protein per lb during the next six months of the trial. They once again concluded that there were no negative effects on renal function. (4)

And the final say on this matter arrived in 2018, when researchers from McMaster University conducted a huge meta-analysis of all of the published data ever carried out relating to high protein diets and kidney issues. The researchers stated that there is no evidence to suggest that a high protein intake will lead to kidney issues. (5)

is too much protein bad for you


high protein diet to build muscle

In the last few decades we’ve seen a few stories in the media where people have reportedly died after drinking a protein shake, or from eating a high protein diet.

Most recently there was a story of a young mother from Australia (2017), and a 20-year old from England (2020).

Shame on the media for using these tragic circumstances to drive clickbait to their websites (i.e. “Person dies from protein shakes!”), because when we dive deeper into these situations we see that both of these individuals had pre-existing kidney issues.

The urea cycle rids the body of the build-up of ammonia, which occurs as a by-product of the kidneys breaking down protein. When a person has UCD (urea cycle disorder) they are unable to expel this ammonia quickly enough, causing it to rise to potentially toxic levels, and that’s what happened here.

UCD is a rare condition, affecting 1 in 80,000 people (roughly 0.1% of the population), and the vast majority of UCD-affected people are identified at birth, so the chances of somebody going through life unaware they have it is even smaller.

However, it does happen, as evidenced above.

One of the things I found peculiar in the aftermath of these tragedies is that lots of pressure was put on whey protein manufacturers to add warning labels to their packaging, advising of the potential dangers of a high protein diet to those who may have kidney issues. I can understand this move, but I do not believe it solves the problem. After all, if a whey protein manufacturer must do that then it also needs to be placed on any protein-based food, too, and still it doesn’t tackle the real issue, which is that these individuals somehow slipped through the net of doctors all the way into their adult lives without ever knowing they had an undiagnosed kidney disease.

Jim Stoppanie too much protein bad


is too much protein bad for you

The vast majority of people can consume a high protein diet without any issues at all.

If that information ever changes, rest assured I’ll update this page.

However, for the 0.1% of the population who have pre-existing kidney issues like UCD, I recommend following the advice of a meta-analysis published in the Annual Review of Nutrition back in 2017 and staying away from a high protein diet (just as your doctor will have advised). (6)

Of course, in some circumstances kidney issues can go completely undiagnosed, like the tragic stories above. I’ve always been a fan of erring on the side of caution where health is concerned, so if you feel like you might have any issues, or if you feel ill every time you have a protein shake or any other protein-based food, go see your doctor and see if you are part of the 0.1%.

As for the rest of you (me included), I recommend you eat your protein, build some muscle, and get fucking hench.

  1. Von Herrath, D., et al. Glomerular filtration rate in response to an acute protein load. Blood Purif (1988).
  2. Knight, E.L., et al. The impact of protein intake on renal function decline in women with normal renal function or mild renal insufficiency. Ann Intern Med (2003).
  3. Poortmans, J.R., et al. Do regular high protein diets have potential health risks on kidney function in athletes?. Int J Sport Nutr Exerc Metab (2000).
  4. Antonio, J., et al. A High Protein Diet Has No Harmful Effects: A One-Year Crossover Study in Resistance-Trained Males. J Nutr Metab (2016).
  5. Devries M. C., et al. Changes in Kidney Function Do Not Differ between Healthy Adults Consuming Higher- Compared with Lower- or Normal-Protein Diets: A Systematic Review and Meta-Analysis. J Nutr (2018).
  6. Kamper A. L., et al. Long-Term Effects of High-Protein Diets on Renal Function. Annu Rev Nutr (2017).

Website members are killing these russhowepti.com training programs, and you can start today!

Full-Body Blitz

Chisel your leanest body to date with this 6-week full-body workout program which is suitable for both beginner and advanced trainees.

RPE 20

Use the Rest Pause technique to add slabs of lean muscle to your fame over the next 10-weeks.

Classic Size

This is an old school 12-week program which uses dropsets, rest pause sets, and classic linear periodization to help you pack on serious muscle mass.

Become War

Carve your action hero body with my modernized version of Sly’s insane Rambo II training regimen!

Get More From Russ!

russ_howe_pti

I’m Russ. I’ve been a personal trainer since 2002, and I own russhowepti.com.

My job is to simplify fitness for my readers.

I send out free fitness tips to over 100,000 men and women every week, all in the same no-nonsense style as the article you’ve just read, so if you enjoyed reading it be sure to jump on my email list below.

Leave a Reply

Your email address will not be published. Required fields are marked *

Get All The Programs

russ howe pti programs

If you like my blog then you’ll absolutely love my training programs. Choose from 20+ russhowepti.com programs to get into the best shape of your life so far!

Learn more.

Newest Programs

  • Definition dropsets program
  • Beach Bum
  • Chisel workout program
  • Musclemania (Russ Howe PTI workout program)

Click here to see all programs.

Newest Blogs