Division of Dermatology, Chulabhorn International College of Medicine, Thammasat University, Pathum Thani, Thailand.
Samitivej Sukhumvit Hospital, Bangkok Dusit Medical Services PLC, Bangkok, Thailand.
Photodermatol Photoimmunol Photomed. 2024 Nov;40(6):e13004. doi: 10.1111/phpp.13004.
Androgenetic alopecia (AGA) affects both men and women, characterized by progressive hair thinning. While current treatments like minoxidil and finasteride have efficacy limitations and side effects, low-level light therapy (LLLT) using red or near-infrared light has emerged as a promising alternative. Recent animal studies suggest potential benefits from green LED light, though human data are sparse.
This study utilized an innovative LED helmet emitting red and green LED light on respective halves of the frontal scalp, delivering an energy density of 40 J/cm over 20 min. Clinical photography, physician evaluations on a 7-point scale, patient satisfaction, and measurements of hair density and hair diameter were employed. Data were analyzed using linear mixed-effects models, with significance set at p < 0.05.
Seventeen participants (47.1% male, 52.9% female, average age 46.47 years) demonstrated notable improvements after 6 months of treatment. Red and green LEDs both significantly increased hair diameter, non-vellus hair density, and satisfaction scores. Notably, the red LED therapy resulted in a statistically significant decrease in vellus hair density and achieved a greater increase in hair diameter compared to the green LED therapy. Minimal adverse effects were reported, primarily consisting of tolerable scalp heat and mild redness.
Both red and green LED therapies effectively enhanced hair growth, increasing density and thickness over 6 months. Red LED demonstrated superior improvements in specific measures. Consequently, both therapies present safe and viable alternatives for the management of AGA, expanding the repertoire of available treatment options.
雄激素性脱发（AGA）影响男性和女性，其特征是头发逐渐稀疏。虽然米诺地尔和非那雄胺等现有治疗方法具有疗效限制和副作用，但使用红光或近红外光的低水平光疗（LLLT）已成为一种有前途的替代方法。最近的动物研究表明绿光 LED 可能具有潜在益处，但人类数据稀缺。
本研究使用了一种创新的 LED 头盔，在前额头皮的两侧分别发出红光和绿光 LED 光，在 20 分钟内提供 40J/cm 的能量密度。使用临床摄影、医生 7 分制评估、患者满意度以及头发密度和直径测量来评估。使用线性混合效应模型进行数据分析，显著性水平设置为 p<0.05。
17 名参与者（47.1%为男性，52.9%为女性，平均年龄 46.47 岁）在治疗 6 个月后表现出显著改善。红、绿 LED 均显著增加了头发直径、非毳毛密度和满意度评分。值得注意的是，与绿光 LED 治疗相比，红光 LED 治疗导致毳毛密度统计学上显著降低，并实现了更大的头发直径增加。报告的不良反应最小，主要包括可耐受的头皮发热和轻度发红。
红、绿 LED 治疗均能有效促进头发生长，在 6 个月内增加密度和厚度。红光 LED 在特定指标上显示出更好的改善。因此，两种疗法均为 AGA 管理提供了安全可行的替代方案，扩大了现有治疗选择的范围。
