LGD-4033 and RAD-140 are the SARMs most frequently reported to cause hair loss in anecdotal bodybuilding accounts, but no controlled study has measured their effect on follicular density. Density tracking during a SARMs cycle provides the first objective data point for whether these compounds actually affect your hair or whether the shedding reports are coincidental.
Why SARMs and Hair Loss Need Objective Data
Selective androgen receptor modulators (SARMs) were designed to bind selectively to androgen receptors in muscle and bone while avoiding androgenic tissues like skin, prostate, and hair follicles. That selectivity is the reason they are marketed as safer alternatives to anabolic steroids for muscle growth.
The problem is that selectivity is relative, not absolute. SARMs are not FDA-approved for any use, and the clinical data on their hair follicle impact is extremely limited. What exists is thousands of anecdotal reports from bodybuilding forums, which are unreliable because people on SARMs cycles are often using multiple compounds simultaneously.
| SARM Compound | Hair Loss Reports (Anecdotal) | Androgenic Rating | Clinical Hair Data |
|---|---|---|---|
| LGD-4033 (Ligandrol) | Moderate frequency | Low | None published |
| RAD-140 (Testolone) | High frequency | Moderate | None published |
| MK-2866 (Ostarine) | Low frequency | Very low | None published |
| S-23 | High frequency | Moderate-high | None published |
Density tracking fills this evidence gap at the individual level. You cannot run a clinical trial on yourself, but you can run a controlled before-and-after measurement series that tells you whether your density changed during and after a SARMs cycle.
Step 1: Establish Your Pre-Cycle Baseline
Start density tracking at least two to four weeks before beginning any SARMs cycle. You need multiple baseline measurements to establish your natural hair loss progression rate.
Take photos of your hairline, temples, crown, and mid-scalp with myhairline.ai at least three times during this pre-cycle window. This establishes whether your hair density is stable, slowly declining, or already in an active shedding phase before the SARM enters the picture.
Record your current Norwood stage. If you are already experiencing androgenetic alopecia (AGA), your baseline progression rate is the critical comparison point. A Norwood 3 patient losing density at 2% per quarter has a different risk profile than a Norwood 1 patient with stable density.
Step 2: Track Weekly During Your Cycle
Once your SARMs cycle begins, increase measurement frequency to weekly. Hair follicle changes happen at the cellular level before they become visible, but AI density measurements can detect shifts in follicular density sooner than the mirror.
Weekly tracking protocol:
- Same day of the week, same time of day
- Same lighting conditions and camera distance
- Log the specific SARM, dosage, and any other compounds in use
- Note any visible shedding changes (shower drain, pillow, brushing)
Most SARMs cycles run 8-12 weeks. At weekly measurement frequency, you will have 8-12 data points during the cycle period. This is enough to identify an accelerating density decline if one occurs.
Step 3: Track Post-Cycle Recovery
Continue weekly measurements for at least eight weeks after discontinuing the SARM. If the compound caused follicular stress, the shedding often continues or peaks in the weeks after the cycle ends as the hormonal environment returns to baseline.
| Tracking Phase | Duration | Frequency | Purpose |
|---|---|---|---|
| Pre-cycle baseline | 2-4 weeks | 2-3 measurements total | Establish natural progression rate |
| On-cycle | 8-12 weeks | Weekly | Detect acceleration |
| Post-cycle recovery | 8 weeks | Weekly | Detect delayed shedding |
| Long-term follow-up | 3-6 months | Biweekly | Confirm recovery or permanent change |
Step 4: Compare Rates, Not Snapshots
The analysis that matters is not "did my density drop" but "did my density drop faster during the cycle than before it." Androgenetic alopecia is progressive. Your hair density may be declining at a natural rate regardless of SARMs use.
If your pre-cycle baseline shows a 1% density decline per month, and your on-cycle data shows a 1.2% decline per month, the difference is within normal measurement variation. But if your on-cycle rate jumps to 3-4% per month, that acceleration is likely attributable to the compound.
Red flags in tracking data:
- Density decline rate doubles or triples during cycle
- New zones of thinning appear that were stable at baseline
- Post-cycle shedding exceeds on-cycle shedding
- Density has not recovered to pre-cycle trajectory by 3 months post-cycle
Step 5: Assess Whether Damage Is Reversible
If your tracking data confirms SARMs-accelerated hair loss, the next question is whether the damage reverses after discontinuation. This is where the post-cycle and long-term tracking data becomes critical.
Temporary shedding (telogen effluvium triggered by hormonal disruption) typically recovers within 3-6 months. If your density returns to the pre-cycle trajectory within this window, the SARMs caused a temporary acceleration but no permanent follicular damage.
If density does not recover and continues declining at an accelerated rate, the SARMs may have triggered a permanent advancement of your androgenetic alopecia pattern. In this case, preventive treatments become urgent. Finasteride halts further loss in 80-90% of men and produces regrowth in 65%. Minoxidil works for 40-60% of users.
For more context on androgen-related hair loss tracking, see anabolic steroid hair loss tracking and tracking hair loss with DHT blood tests.
Get Your Pre-Cycle Baseline
If you are considering a SARMs cycle and have any concern about hair loss, get your baseline density measurement now with the free tool at myhairline.ai/analyze. The data you collect before the cycle is the most important data you will have.
Medical Disclaimer: This article is for informational purposes only and does not constitute medical advice. SARMs are not FDA-approved for human use and are sold as research chemicals. This article does not endorse the use of SARMs. Always consult a qualified healthcare provider before using any performance-enhancing compounds.