Editorial update: September 12, 2026. Published by ReHair.
Low-level light or laser therapy (LLLT) is an option to discuss for some forms of hair loss, not a universal answer to shedding. Research in adults with androgenetic alopecia has reported improved hair density, but that does not establish the same result for every person or every device.
What the evidence actually covers
A 2019 systematic review evaluated randomized trials in androgenetic alopecia. Its findings should be read in that setting. They are not proof that an unspecified ReHair model treats every cause of hair loss. Before relying on a study, check the participants, device, comparison group, follow-up period and outcome measured.
Do not turn a study into a promise
A hair-count measurement is different from a visible cosmetic change, and neither is a guarantee of satisfaction. An average result cannot predict your individual response. This article does not promise a percentage increase, a fixed regrowth date or a permanent cure. More power, more diodes or a longer session should not be assumed to produce better results.
Questions to take to an appointment
- What is the likely cause of my hair loss?
- Is a light-based device appropriate alongside my current care?
- What outcome would be useful to track, and when should we review it?
- Which changes or symptoms should prompt me to stop and seek advice?
Check the exact product before ordering
Match any study or regulatory statement to the exact device identity and intended use. Ask for the model-specific instructions and warnings before choosing a schedule. You can review the ReHair cap listing and contact ReHair support for documentation; this overview is not a substitute for that documentation.
Sources
Related reading
- Laser Caps vs Laser Combs: How to Compare the Formats
- Using a ReHair Laser Comb: Check Your Model Instructions
General information, not an individual diagnosis or treatment prescription. Follow the instructions for your exact device and seek qualified advice for personal medical questions.