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If you’re looking for ways to treat thinning hair, you may have heard about laser hats. Some, like the Capillus laser cap, look like a regular baseball hat until you look underneath and see rows of red lights.
So, how does light therapy work to regrow hair? Let’s take a look.
What is a hair growth cap?
A number of companies sell hair growth caps that claim to regrow hair and reduce the progression of hair loss caused by androgenic alopecia.
This type of hereditary hair loss is also known as pattern baldness, which affects both men and women. Several hair regrowth devices like the Capillus laser cap have been approved by the US Food and Drug Administration (FDA) to treat this type of hair loss.
A form of low-level laser therapy (LLLT), products like the Capillus stimulate hair follicles to produce thicker and fuller hair. If you’re having trouble picturing them, laser hats have dome inserts with rows of lights. For instance, the CapillusPro has 272 red laser diodes (LDs), while others use LDs mixed with LED lights (Lueangarun, 2021).
How does light trigger hair growth?
Studies suggest that red to infrared light may activate hair follicle cells. This can trigger hair growth, shifting hairs from a resting phase to the growth phase. LLLTs may also make hair thicker and decrease shedding, potentially improving the appearance of hair loss (Pillai, 2021).
Benefits of laser caps
Many studies suggest potential benefits from laser caps. One small study found men who wore an LLLT helmet device saw a 35% increase in hair growth compared to those using a sham helmet device (Lanzafame, 2013).
Another study by the same research team found similar results in women with pattern baldness, though it’s important to note the studies were funded by a company promoting LLLT use (Lanzafame, 2014).
One study of women with female pattern hair loss found using a previous Capillus product (Handi-Dome Laser) for 30 minutes every other day led to a 51% increase in the number of hairs after 17 weeks (Egger, 2020).
A recent study that reviewed decades of research found that LLLT may be effective for pattern hair loss, but additional long-term studies and comparisons between devices are needed (Lueangarun, 2021).
Hair shedding vs. hair loss: what’s the difference?
Do hair growth caps work?
Laser hair removal practitioners have known for years that if a laser setting isn’t high enough, it can stimulate hair follicles rather than damage them.
Research suggests that laser technology may promote hair growth. Generally, it takes three months to a year to see new hair or changes to your hairline. That said, what works for some doesn’t work for everyone. Consumer reviews of these products are often mixed.
Manufacturers note that LLLT works best in people with androgenic alopecia who are just starting to notice thinning. Capillus and other brands may not be as helpful in cases of complete baldness where there are no follicles to stimulate (Pillai, 2021).
Side effects of hair growth caps
The primary side effect of LLLT is initial hair shedding. This may seem alarming, but hair shedding is expected at the beginning since these devices push out hairs to allow for more growth.
Initial hair thinning usually tapers off with new hair growth. A review of studies found no major side effects and minor reactions like itching, scalp tenderness, or irritation (Egger, 2020).
How to use the Capillus laser cap
The Capillus laser cap is a dome insert that can fit under most baseball caps. If you’re trying it for the first time to treat hair loss, here are the basic instructions (Capillus, 2022):
- Charge the device (for portable use)
- Place the dome on the head underneath the provided cap or another hat (if desired)
- Press and hold the power button to start treatment
- Lights turn off automatically after the programmed time
- Repeat each day for six minutes (newer, continuous-wave models)
As with other laser therapy devices, avoid staring into laser lights. The lights may also turn off if the device isn’t correctly positioned on your head. If you have cancerous lesions on your head, avoid using LLLT devices like Capillus laser therapy as the impact of red light isn’t fully known (Hamblin, 2018).
Preventing and treating hair loss on Accutane (isotretinoin)
How much does the Capillus laser cap cost?
Capillus offers three models that vary in cost (Capillus, 2022):
- CapillusOne, $1,099
- CapillusPlus, $1,999
- CapillusPro, $2,999
The physical difference between models is the number of laser diodes (112, 202, or 272) with energy outputs ranging from 410–1,360 mW. All models feature device inserts that can fit into a variety of caps, plus a battery pack for portability.
The bottom line
In general, LLLT may be a viable, non-surgical treatment for restoring hair loss caused by alopecia. When searching for a product, look for one FDA-approved for hair loss.
For optimal results, LLLT is often combined with other hair loss treatment options like microneedling or medication. Talk to a healthcare professional who can help create a treatment plan that works for you (Gentile, 2020).
- Capillus. (2020). Capillus Limited Warranty. Retrieved from https://support.capillus.com/hc/en-us/articles/360047536213-Capillus-Limited-Warranty
- Capillus. (2022). Discover Capillus laser caps and laser therapy for hair regrowth. Retrieved from https://www.capillus.com/pages/capillus-laser-caps
- Egger, A., Resnik, S. R., Aickara, D., et al. (2020). Examining the safety and efficacy of low-level laser therapy for male and female pattern hair loss: A review of the literature. Skin Appendage Disorders, 6(5), 259–267. doi:10.1159/000509001. Retrieved from https://www.karger.com/Article/FullText/509001
- Gentile, P., Dionisi, L., Pizzicannella, J., et al. (2020). A randomized blinded retrospective study: The combined use of micro-needling technique, low-level laser therapy and autologous non-activated platelet-rich plasma improves hair re-growth in patients with androgenic alopecia. Expert Opinion on Biological Therapy, 20(9), 1099–1109. doi:10.1080/14712598.2020.1797676. Retrieved from https://www.tandfonline.com/doi/abs/10.1080/14712598.2020.1797676?journalCode=iebt20
- Hamblin, M. R., Nelson, S. T., & Strahan, J. R. (2018). Photobiomodulation and cancer: What is the truth? Photomedicine and Laser Surgery, 36(5), 241–245. doi:10.1089/pho.2017.4401. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5946726/
- Lanzafame, R. J., Blanche, R. R., Bodian, A. B., et al. (2013). The growth of human scalp hair mediated by visible red light laser and led sources in males. Lasers in Surgery and Medicine, 45(8), 487–495. doi:10.1002/lsm.22173. Retrieved from https://pubmed.ncbi.nlm.nih.gov/24078483/
- Lanzafame, R. J., Blanche, R. R., Chiacchierini, R. P., et al. (2014). The growth of human scalp hair in females using visible red light laser and led sources. Lasers in Surgery and Medicine, 46(8), 601–607. doi:10.1002/lsm.22277. Retrieved from https://pubmed.ncbi.nlm.nih.gov/25124964/
- Lueangarun, S., Visutjindaporn, P., Parcharoen, Y., et al. (2021). A Systematic Review and Meta-analysis of Randomized Controlled Trials of United States Food and Drug Administration-Approved, Home-use, Low-Level Light/Laser Therapy Devices for Pattern Hair Loss: Device Design and Technology. Journal of Clinical and Aesthetic Dermatology, 14(11), E64-E75. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8675345/
- Pillai, J. K. & Mysore, V. (2021). Role of low-level light therapy (LLLT) in androgenetic alopecia. Journal of Cutaneous and Aesthetic Surgery, 14(4), 385. doi:10.4103/jcas.jcas_218_20. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8906269/
- Tabaie, S. M., Berenji Ardestani, H., & Azizjalali, M. H. (2016). The effect of one session low-level laser therapy of extracted follicular units on the outcome of hair transplantation. Journal of Lasers in Medical Sciences, 7(1), 26–29. doi:10.15171/jlms.2016.06. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4908985/
Dr. Chimene Richa is a board-certified Ophthalmologist and Senior Medical Writer/Reviewer at Ro.