Hair Growth

630nm Research

630–690 nm LED Helmet Boosts Hair Density and Thickness

Fifty people with hair loss wore a helmet emitting 630–690 nm red LED light for 20 minutes daily over 6 months, leading to significantly denser and thicker hair, less oily scalp, and improved overall scalp health for over 70% of users, offering a safe, non-invasive way to combat thinning hair.

Review: 630–660 nm Red Light Stimulates Hair Regrowth

A review of research explains how red light in the 630–660 nm range, often via LEDs, promotes hair growth by boosting cell energy, improving blood flow to follicles, and activating growth pathways, with studies showing increased hair count in people with pattern hair loss.

HeroSeries panels and face masks use 630nm red light

650 nm Laser and LED Helmet Increases Hair Density

In a 24-week trial with 40 people experiencing hair loss, using a helmet with 650 nm laser and 630/660 nm LEDs for 18 minutes daily boosted hair density by 17% and thickness by 13% compared to placebo, with no side effects, suggesting it stimulates follicles to grow more hair.

650 nm Laser Device Boosts Hair Counts in Women

A double-blind trial on 44 women with pattern hair loss used a cap with 272 lasers at 650 nm for 30 minutes every other day over 17 weeks, resulting in a 64% increase in thick hairs vs 12% in the sham group, safely promoting regrowth without issues.

650 nm Red LED Light Promotes Hair Growth in Lab Model

In lab tests on human hair follicles from people with hair loss, treating with 650 nm red LED light for 5 minutes every other day led to longer hair shafts, more growing follicles (45% stayed in growth phase vs 33% in controls), and higher cell activity, potentially helping treat baldness by activating anti-inflammatory and energy-boosting genes.

650 nm Laser and LEDs Improve Hair Coverage

In a 24-week study on 100 patients, a helmet with 650 nm lasers and 660 nm LEDs used three times a week for 30 minutes increased hair coverage by 14% vs 12% in sham, enhancing density through better follicle energy and growth signals.

HeroHat Laser uses 650nm red light

660 nm LED (Dual Wavelength) Increases Hair Density in Androgenetic Alopecia

In a double-blind randomized trial with patients suffering from hair loss, using an LED cap emitting 625–660 nm red light for 10 minutes daily over 16 weeks led to 28.5 more hairs per cm² compared to sham, proving safe and effective for boosting hair growth.

660 nm LED Reduces DHT for Hair Loss Treatment

Lab studies showed that 620 and 660 nm LED light stimulates nitric oxide and reactive oxygen species, which inhibit the production of DHT (a hormone causing hair loss), providing a mechanism for how red light therapy promotes hair regrowth in androgenetic alopecia.

660 nm LED Stimulates Dermal Papilla Cells for Hair Growth

In vitro tests on human hair cells found that 660 nm LED light boosts cell proliferation through Wnt/β-catenin and ERK pathways, leading to longer hair follicles and suggesting benefits for treating hair thinning.

655 nm LED (with Laser) Boosts Hair Counts in Men

A double-blind trial on men with pattern baldness using a helmet with 655 nm LEDs (practical overlap with 660nm) and lasers every other day for 16 weeks resulted in a 39% increase in hair counts, with no side effects, supporting red light for hair regrowth.

Near-infrared wavelengths are excluded from this page because most hair growth research uses 630-660nm red light.

It is also worth noting most studies co mbine lasers and LEDs which is why we sell both the HeroHat Laser and the HeroHat LED (with a discount if you purchase both together)