Safety of Selective Androgen Receptor Modulators (SARMs) for Muscle Mass and Athletic Performance
SARMs are not safe for improving muscle mass or athletic performance and should not be used outside of clinical trials due to significant health risks and lack of FDA approval.
What Are SARMs?
Selective Androgen Receptor Modulators (SARMs) are non-steroidal compounds designed to selectively activate skeletal muscle androgen receptors while potentially avoiding some adverse effects of traditional androgenic steroids 1. They were originally developed for treating muscle wasting conditions, osteoporosis, and certain cancers 2, 3.
Safety Concerns and Risks
Lack of Regulatory Approval
- No SARM has received FDA approval for any medical use 4, 5
- SARMs are typically sold illegally online as "research chemicals" or supplements 6
Documented Adverse Effects
Recent studies have identified significant health risks associated with SARM use:
- Cardiovascular effects: Hypertension, arrhythmias, and myocarditis 7, 5
- Hormonal disruption: Over 50% of users report decreased testicular size and testosterone suppression 4, 5
- Hepatotoxicity: Multiple case reports of drug-induced liver injury 5
- Mood disturbances: Mood swings reported by more than half of users 4
- Other effects: Acne, tendon damage, and impaired insulin sensitivity 4, 5
Quality Control Issues
A 2024 study analyzing SARMs purchased online found 6:
- Only 70% of products contained the labeled SARM
- 23% contained a different SARM than advertised
- 30% contained undeclared pharmaceutical substances (including tamoxifen, clomifene, testosterone)
- Dosage varied from 30-90% of the label claim
Current Medical Consensus
The ESPEN guidelines (2021) explicitly state: "There are insufficient consistent clinical data to recommend currently approved androgenic steroids to increase muscle mass" 1. This recommendation applies even more strongly to SARMs, which lack approval altogether.
Athletic governing bodies have established comprehensive anti-doping programs that include regular testing for SARMs, as they are classified as prohibited performance-enhancing substances 7.
Prevalence of Use
Despite safety concerns, SARMs have gained popularity:
- Estimated 1-3% prevalence among athletes 5
- 98.5% of users are male, primarily aged 18-29 4
- Over 90% of users acquire SARMs via the internet without physician consultation 4
Risk vs. Benefit Analysis
While over 90% of users report increased muscle mass and satisfaction with results 4, these perceived benefits must be weighed against:
- Significant documented adverse effects affecting multiple organ systems
- Unknown long-term health consequences due to lack of comprehensive studies
- Quality control issues leading to unpredictable dosing and contamination
- Legal implications of using prohibited substances
Conclusion
Based on the most recent and highest quality evidence, SARMs present significant health risks without proven safety for improving muscle mass or athletic performance. Their use should be limited to controlled clinical trials investigating legitimate medical applications such as treating muscle wasting in cancer patients 1.
For individuals seeking to improve muscle mass, evidence-based approaches including proper nutrition and structured resistance training programs remain the safest and most effective options.