Synbiotic HQP08 Supplementation for Hair Loss and Depressive Symptoms: An Open-Label Pilot Study of Clinical Outcomes and Gut Microbiome Changes
In 32 adults without a control group, synbiotic HQP08 (B. longum HK003) yielded self-reported hair loss improvement in 62.5% of participants at 8 weeks, but causal attribution is impossible without a control arm.
| Population | Adults aged 18–50 years with self-reported hair loss, no recent use of minoxidil, finasteride, antibiotics, or corticosteroids (n=32, Prince of Wales Hospital, Hong Kong) |
|---|---|
| Intervention | HQP08 (synbiotic: B. longum HK003 20×10⁹ CFU + FOS + GOS + pumpkin seed oil powder + xylitol), one sachet/day for 8 weeks |
| Comparator | None (single-arm open-label pilot; no placebo or active control) |
| Outcome | Self-reported global improvement (PGI-C ≤3); Hair loss severity (PGI-S); 60-second hair count; Depressive symptoms (PHQ-9); Anxiety (GAD-7); Response predictor: age (OR per year); B. longum HK003 engraftment (metagenomics) |
Summary of findings
| Outcome | Effect | 95% CI | Certainty | Clinical relevance | Notes |
|---|---|---|---|---|---|
| Self-reported global improvement (PGI-C ≤3) | Response rate 62.5% (20/32); in the comparator, in the CI reported | — | Very low | — | 1 studies |
| Hair loss severity (PGI-S) | Median change -1.0, p=0.0008; in the CI, in the comparator | — | Very low | — | 1 studies |
| 60-second hair count | Median change -1.5, p=0.0048; in the CI, in the comparator | — | Very low | — | 1 studies |
| Depressive symptoms (PHQ-9) | Reported as secondary; in the CI, in the comparator; full data not provided in excerpt | — | Very low | — | 1 studies |
| Anxiety (GAD-7) | Reported as secondary; in the CI, in the comparator; full data not provided in excerpt | — | Very low | — | 1 studies |
| Response predictor: age (OR per year) | OR 0.86, 95% CI 0.73-0.98, p=0.037 (younger age favors response) | — | Low | — | 1 studies |
| B. longum HK003 engraftment (metagenomics) | Exploratory; in the effect size or CI reported in excerpt | — | Very low | — | 1 studies |
Context
Hair loss carries substantial psychosocial burden and existing pharmacological options face tolerability and adherence limitations. The gut–skin axis has been proposed as a mediator of systemic inflammation affecting hair follicles, motivating microbial intervention research.
What the study showed
At week 8, 62.5% (20/32) achieved PGI-C ≤3; of these, 9.4% reported 'much improved' and 53.1% 'minimally improved'. Hair loss severity (PGI-S) showed a median reduction of −1.0 point (p=0.0008); 60-second hair count showed a median reduction of −1.5 hairs shed (p=0.0048; response rate 68.8%, 22/32). Younger age independently predicted response (OR per year 0.86; 95% CI 0.73–0.98; p=0.037). No 95% CIs were reported for the primary hair-count endpoints beyond the age OR.
How it was done
Single-arm open-label pilot, 8-week intervention, with fecal samples collected at baseline and 4 weeks post-intervention (week 12) for shotgun metagenomics. Thirty-five participants enrolled; 32 completed week-8 clinical assessment. No formal power calculation was performed; completers-only analysis with no intention-to-treat approach.
Effect magnitude
Age-response OR: 0.86 per year (95% CI 0.73–0.98). Absolute effect sizes for PGI-S and hair count are reported as medians only, without 95% CIs. Clinical magnitude cannot be adequately quantified without a comparator.
Risk of bias
No control group prevents distinguishing product effect from placebo response, regression to the mean, or natural hair cycle variation. Small sample (n=32) with no power calculation. Primary outcomes are self-reported (PGI-C/PGI-S), subject to response bias and expectation effects. Proprietary product composition (non-microbial ingredient quantities undisclosed) precludes replication. Diet was neither controlled nor recorded. No formal risk-of-bias tool (RoB 2/ROBINS-I) was applied by the authors. Metagenomics collected 4 weeks after intervention end, not at treatment completion.
What this study does NOT prove
This study does not prove that HQP08 causes hair loss reduction; without a control, observed improvement may be entirely attributable to placebo effect or spontaneous remission. Results are not generalizable beyond young adults in Hong Kong with self-reported hair loss and no formally diagnosed alopecia areata.
In clinical practice
Current data do not support clinical recommendation of HQP08 for hair loss. Absence of a control arm prevents causal attribution. Clinicians should await a placebo-controlled RCT before considering this synbiotic as a therapeutic option.
Limitations
No control group prevents distinguishing product effect from placebo response, regression to the mean, or natural hair cycle variation. Small sample (n=32) with no power calculation. Primary outcomes are self-reported (PGI-C/PGI-S), subject to response bias and expectation effects. Proprietary product composition (non-microbial ingredient quantities undisclosed) precludes replication. Diet was neither controlled nor recorded. No formal risk-of-bias tool (RoB 2/ROBINS-I) was applied by the authors. Metagenomics collected 4 weeks after intervention end, not at treatment completion.
What is still missing
A double-blind placebo-controlled RCT with adequate power, objective hair endpoints (trichoscopy, phototrichogram), and stratification by alopecia type is needed to establish efficacy and identify responsive subgroups.
Technical appendix
Version history
- 1.0 · 2026-10-19 — Auto-generated under Evidence Standard v1.0