Comparative effectiveness of low-level laser therapy for adult androgenic alopecia: a system review and meta-analysis of randomized controlled trials

    January 2019 in “Lasers in Medical Science
    Kao-Hsiang Liu, Donald J. Liu, Yu-Tsung Chen, Szu Ying Chin
    Image of study
    TLDR Low-level laser therapy significantly increases hair density in adults with hair loss, with low-frequency treatment being more effective.
    In 2019, a systematic review and meta-analysis of 8 studies, including 11 double-blinded randomized controlled trials with 667 participants, found that low-level laser therapy (LLLT) significantly increased hair density in adults with androgenic alopecia. The treatment was effective for both genders, with both comb- and helmet-type devices, and in both short- and long-term treatment courses. Interestingly, low-frequency LLLT treatment resulted in a more significant increase in hair growth than high-frequency treatment. However, the study noted several limitations, including small sample sizes in most trials, diverse wavelengths and power used in LLLT, and inconsistent subject characteristics across trials. The exact mechanisms of how LLLT promotes hair growth remained unclear.
    View this study on →

    Cited in this study