Do Steroids Affect Your Kidneys? 6 Facts & the Real Danger

Steroids and kidneys in three numbers

Three study figures frame how steroids affect your kidneys.

Study figures come from PubMed papers. Where a point is practice rather than a trial, we say so. This page is about anabolic steroids, not prednisone.

What this guide to steroids and kidneys covers

Do steroids affect your kidneys often? The population data

The only population study comes from Iraqi Kurdistan. Over 9 years, about 25,000 regular bodybuilders were followed, with 26% reporting steroid use (PMID 32375656).

Fifteen bodybuilders had kidney biopsies. Rates of FSGS, membranous and other glomerular diseases were not statistically different from the general male population (PMID 32375656).

The one clear exception was nephrocalcinosis from veterinary grade vitamin D injections, at one case per 314 injectors (PMID 32375656). A separate case report describes renal failure from the same cause in a bodybuilder (PMID 24786891).

The HAARLEM cohort, which followed 100 men through a cycle, describes a distinct but limited impact on kidney function (PMID 35938779).

FSGS: the kidney disease linked to steroids

In 2010, pathologists at Columbia described 10 bodybuilders with focal segmental glomerulosclerosis after long term steroid abuse. Mean body mass index was 34.7 (PMID 19917783).

They presented with heavy protein loss in urine, a mean of 10.1 g a day, and a mean serum creatinine of 3.0 mg per dl. Three had nephrotic syndrome (PMID 19917783).

Biopsies showed FSGS in 9 of 10, and 7 had at least 40% tubular atrophy and scarring (PMID 19917783).

The authors proposed two drivers: glomeruli overworked by very high lean mass, plus a possible direct toxic effect of the drugs (PMID 19917783).

How do steroids affect your kidneys? The mechanisms

A systematic review covered 21 clinical and experimental papers. Anabolic steroids can induce or aggravate acute kidney injury, chronic kidney disease and glomerular toxicity (PMID 31151420).

The pathways named were renin angiotensin aldosterone activation, endothelin, reactive oxygen species, pro fibrotic signals such as TGF beta 1, and inflammatory cytokines (PMID 31151420).

Blood pressure is part of it. During the HAARLEM cycle, systolic pressure rose 6.87 mmHg and diastolic 3.17 mmHg, returning to baseline a year after the start (PMID 35014715).

Growth hormone, often stacked with steroids, changes kidney size and filtration, but the review found no conclusive evidence of harm at athlete doses (PMID 31151420).

The creatinine trap: why the standard test misleads

Creatinine comes from muscle. In 170 healthy people, serum and urinary creatinine tracked lean mass more closely than body weight (PMID 18235143).

Active people had higher serum creatinine, 1.04 versus 0.95 mg per dl, with no difference in cystatin C (PMID 18235143).

The FSGS authors made the same point. Creatinine is expected to rise with muscle mass in bodybuilders, so kidney damage in this group is likely under recognised (PMID 19917783).

Cystatin C: the marker that fits muscular men

Cystatin C is produced by all cells at a steady rate and is independent of muscle mass (PMID 18235143).

A 2023 study compared 12 bodybuilders using steroids plus supplements with 12 using supplements only, after about 3 years of use (PMID 37680426).

Creatinine based eGFR did not differ: 119.7 versus 122.1 ml per min. Cystatin C based eGFR was lower in the steroid group, and the combined equation gave 121.8 versus 126.3 (PMID 37680426).

Urine albumin and protein ratios were also higher in the steroid group (PMID 37680426).

Steroids and kidneys vs creatine and protein

Creatine. A meta-analysis of creatine trials found no renal damage at the studied doses and durations (PMID 31375416).

Creatine does raise serum creatinine slightly, because creatine converts to creatinine. That is a measurement effect, not kidney injury (PMID 31375416).

Protein. In 28 trials with 1,358 healthy adults, higher protein intake did not change kidney filtration compared with lower intake (PMID 30383278).

Higher protein diets, 1.5 g per kg or more, produced a trivially higher GFR after the trial. The change over time did not differ (PMID 30383278).

Steroids and kidneys after stopping: do they recover?

In the FSGS series, 7 patients stopped steroids and received blood pressure drugs that block the renin angiotensin system. Creatinine stabilised or improved and proteinuria fell (PMID 19917783).

One patient restarted steroids and relapsed with proteinuria and renal insufficiency. One of eight with follow up progressed to end stage renal disease (PMID 19917783).

In HAARLEM, effects on liver and kidney function were limited, and most effects were reversible after the cycle (PMID 35938779).

Danish steroid users had 0.81 hospital contacts a year against 0.36 in controls, and mortality three times higher (PMID 30460728).

Steroids and kidneys: how to read the panel

For reference, the CKD Prognosis Consortium supports 60 ml per min as the chronic kidney disease threshold. Risk already rose in the 60 to 74 range (PMID 22038337).

Steroids and kidneys: warning signs that need a doctor

Verdict: 6 facts about steroids and kidneys

1. Serious damage is rare. FSGS 3.4 vs 2.0 per 100,000, not significant (PMID 32375656).

2. It is documented. 10 bodybuilders with FSGS after long term use (PMID 19917783).

3. Creatinine misleads. It tracks lean mass, not kidneys (PMID 18235143).

4. Cystatin C catches it. Lower in steroid users when creatinine was not (PMID 37680426).

5. Creatine and protein are not the cause. No renal damage in meta-analyses (PMID 31375416, 30383278).

6. Stopping helps. Creatinine stabilised and proteinuria fell after stopping (PMID 19917783).