LEDs vs Lasers for Hair Regrowth: What the Science Really Say

At-home red light therapy can feel confusing. Do you need a laser? Are LEDs strong enough? Let’s make it clear, science-first, and practical for your routine.

What's the difference between lasers and LEDs?

Lasers produce “coherent” light: waves that travel in lockstep, tightly focused into a narrow beam. LEDs are “non-coherent”: the waves are not locked together, and the beam spreads out more. That sounds technical, but here’s the takeaway that matters for you: your cells don’t require coherence to respond. For photobiomodulation, what drives results are the basics, the precise wavelength, the right dose, and consistent use - not whether the photons came from a laser or an LED. In comparative reviews, when wavelength and dose are matched, both sources trigger the same cellular pathways and deliver comparable outcomes.1,2

Does the light source matter for hair growth?

The story of light therapy for hair started with lasers. Precise, powerful, and perfectly coherent. But as research progressed, something interesting emerged: coherence didn't matter as much as was thought. LEDs, with their non-coherent light, delivered the same biological effects when wavelength and dose were matched. Science evolved, and so did the name. In 2016, "low-level laser therapy" officially became "photobiomodulation," reflecting a broader understanding: it's not about the source, it's about the dose, the wavelength, and the consistency.3

This shift wasn't just academic, it opened the door to practical, at-home devices that prioritize coverage, safety, and real-world usability. For scalp health and hair regrowth, what matters is reaching thousands of follicles with the right amount of light, repeatedly, over time.

Which one is better for hair growth?

The short answer: LEDs. Let us explain why.

LEDs spread light across a broader area than lasers, making it easier to deliver even coverage over your scalp. They work within lower irradiance ranges, perfect for home use when used as directed. When wavelength and dose are matched, your cells respond the same way to LED and low-level laser light, coherence isn't required for photobiomodulation to work.1,2

What actually matters for results

The right wavelengths: Red light at 650 nm is the most studied for scalp.4 These wavelengths are absorbed by chromophores like cytochrome c oxidase, supporting mitochondrial energy production and healthy cell signaling.2

Dose, not hype: Photobiomodulation follows a biphasic dose response. Too little under-doses, too much can reduce benefits.5 Real-world protocols use modest irradiance delivered consistently over time.

Coverage and consistency: Hair regrowth means reaching thousands of follicles repeatedly. Uniform scalp coverage and regular use drive visible outcomes in at-home devices.7,8

LEDs vs lasers: a practical comparison

• Coverage: LEDs emit light more diffusely than lasers, helping deliver even dose across larger areas, ideal for LED array caps.1
• Safety: LEDs commonly operate within non-thermal photobiomodulation windows, lowering the risk of heat-related irritation when used as directed.2,5
• Mechanisms: When wavelength and dose are matched, non-coherent LEDs and low-level lasers engage the same mitochondrial and redox pathways with comparable outcomes.1,2
• Outcomes: Randomized Controlled Trials and meta-analyses show increased hair counts and diameter with at-home low-level light therapy across treatments;8 results depend more on parameters and adherence than on coherence.7,8

Mechanisms, made simple

When red or near-infrared photons reach the follicle’s cellular engines, they can:2,9

• Support mitochondrial electron transport and ATP production
• Modulate nitric oxide, ROS, and calcium signaling
• Activate transcription factors that influence cell survival, repair, and proliferation

Think of photobiomodulation as light used gently and precisely. What matters most is choosing the right wavelength, how strong it is at the skin, how much total light you give, and for how long.10 Get those basics right and the results follow.

Net effect: a microenvironment more supportive of anagen maintenance (the active growth phase of the hair follicle) and follicle vitality.

What the research says on hair growth

Clinical evidence

Systematic reviews and meta-analyses report meaningful gains in terminal hair counts (the thick, coarse, and pigmented hair) with at-home low-level light therapy LED array devices,8 typically using red wavelengths around 650 nm on regular schedules.7,8

Parameters that keep coming up

Red light at 650 nm and session doses of a few J/cm² per treatment, several times per week, over months. Consistency is critical; think ritual, not a one-off.4,8

How to build your ritual

• Aim for 10 minutes per session, several times a week - always follow the directions for use
• Keep a steady schedule for at least 12–24 weeks
• Pair with scalp care basics: gentle cleansing, massage, and lifestyle foundations like sleep, nutrition, and stress management
• Track progress monthly with consistent lighting and angles

If you have a diagnosed hair disorder or are taking medications that may affect hair growth, talk to a qualified healthcare professional before you start.

Why BON CHARGE

Wellness is a practice. Our approach is to translate robust science into intuitive, repeatable rituals you can do at home. Designed for comfort, coverage, and credible dosing. The goal isn’t a miracle overnight. It’s steady support for scalp health and fuller-looking hair over time, powered by light and consistency.

Disclaimer

BON CHARGE: This content is for general education and is not medical advice. Our products are not intended to diagnose, treat, cure, or prevent any disease. Always follow product instructions and consult a qualified healthcare professional for guidance tailored to you. Individual results may vary.

References

1. Heiskanen, V. & Hamblin, M.R. Photobiomodulation: lasers vs. light-emitting diodes? Photochem. Photobiol. Sci. 17, 1003–1017 (2018). doi:10.1039/C8PP00176F
2. de Freitas, L.F. & Hamblin, M.R. Proposed mechanisms of photobiomodulation or low-level light therapy. IEEE J. Sel. Top. Quantum Electron. 22, 7000417 (2016). doi:10.1109/JSTQE.2016.2561201
3. Hamblin, M.R. Photobiomodulation or low-level laser therapy. J. Biophotonics 9, 1122–1124 (2016). doi:10.1002/jbio.201670113
4. Yang K, Tang Y, Ma Y, Liu Q, Huang Y, Zhang Y, Shi X, Zhang L, Zhang Y, Wang J, Zhu Y, Liu W, Tan Y, Lin J, Wu W. Hair Growth Promoting Effects of 650 nm Red Light Stimulation on Human Hair Follicles and Study of Its Mechanisms via RNA Sequencing Transcriptome Analysis. Ann Dermatol. 2021;33(6):553-561. doi:10.5021/ad.2021.33.6.553
5. Zein, R., Selting, W. & Hamblin, M.R. Review of light parameters and photobiomodulation efficacy: dive into complexity. J. Biomed. Opt. 23, 120901 (2018). doi:10.1117/1.JBO.23.12.120901
6. Torres, A.E. & Lim, H.W. Photobiomodulation for the management of hair loss. Photodermatol. Photoimmunol. Photomed. 37, 91–98 (2021). doi:10.1111/phpp.12649
7. Avci, P., Gupta, A., Sadasivam, M., Vecchio, D., Pam, Z., Pam, N. & Hamblin, M.R. Low-level laser (light) therapy for treatment of hair loss. Lasers Surg. Med. 46, 144–151 (2014). doi:10.1002/lsm.22170
8. Liu, K.H., Liu, D., Chen, Y.T. & Chin, S.Y. Comparative effectiveness of low-level laser therapy for adult androgenic alopecia: a systematic review and meta-analysis of randomized controlled trials. Lasers Med. Sci. 34, 1063–1069 (2019). doi:10.1007/s10103-019-02723-6
9. Hamblin, M.R. Mechanisms and applications of the anti-inflammatory effects of photobiomodulation. AIMS Biophys. 4, 337–361 (2017). doi:10.3934/biophy.2017.3.337
10. Hamblin, M.R. & Demidova, T.N. Mechanisms of low level light therapy. Proc. SPIE 6140, 614001 (2006). doi:10.1117/12.646294