What Frequency Is Best for Red Light Therapy?
Many people researching red light therapy wonder if pulsed light is better than continuous light. This idea comes from a 2010 Harvard study by Dr. Michael Hamblin, which showed pulsed light was more effective for low-level laser therapy (LLLT) because it helped lasers reduce heat-related side effects.
This finding has been widely cited and interpreted to mean that pulsed light is superior for all types of light therapy, including LED devices. However, this is a misconception. The original study only applies to lasers, which produce highly focused, coherent light. Lasers can overheat the skin if used continuously, which is why pulsing provides a way to manage heat while still delivering therapeutic energy.
Modern LED red light therapy devices work differently. LEDs produce incoherent light, which spreads evenly over a larger area and generates far less heat. Because of this, pulsing does not provide the same benefit it does for lasers. In fact, pulsed LEDs can actually reduce the total energy delivered to the skin and underlying tissue, making the therapy less effective. There is currently no strong scientific evidence supporting pulsed LED light over continuous LED light. Continuous exposure remains the standard recommended method for achieving consistent results.
How Frequency Is Measured in Red Light Therapy
Frequency in red light therapy is measured in Hertz (Hz), which indicates how many times per second the light pulses on and off:
-1 Hz equals one on/off cycle per second
-Higher Hz values indicate faster pulsing
-Continuous wave light effectively has 0 Hz, since it does not pulse
Frequency only applies to pulsed light. Most modern LED red light therapy devices use continuous light, meaning frequency is not a determining factor in effectiveness.
Why Pulsed Light Does Not Improve LED Therapy
The misconception that pulsed light is superior comes from misinterpreting laser research. Lasers produce coherent, focused light that can overheat skin. Pulsing allows heat to dissipate, which prevents burns while maintaining benefits. LEDs, however, generate incoherent, dispersed light and do not pose the same heat risks. Pulsing an LED is therefore unnecessary and can even reduce the total energy delivered to the tissue.
Another factor is irradiance, or the amount of usable light energy reaching the skin. LEDs deliver energy differently than lasers, and consistent, uninterrupted exposure ensures maximum energy absorption. Pulsing can reduce this energy transfer, meaning you may see slower or less noticeable results.
Despite this, some of our LED devices now offer adjustable pulse frequencies for users who want to experiment. While pulsing is not required for effective therapy, having the option allows customers to tailor their experience and explore what feels best for their individual routine.
What Actually Matters for Red Light Therapy Results
Rather than focusing on pulsing or frequency, research shows the most important factors are:
1. Wavelength
-Red light: approximately 630 to 660 nanometers for skin health, collagen stimulation, and rejuvenation
-Near-infrared (NIR): approximately 830 to 880 nanometers for deeper tissue, muscle recovery, and joint support
2. Irradiance
-Measures how much usable light energy reaches your skin
-Higher irradiance generally produces faster and more noticeable results
-Wattage alone is not a reliable indicator
3. Consistency
-Recommended session length is 10 to 20 minutes, three to seven times per week
-Continuous, consistent exposure yields better results than inconsistent or pulsed use
Summary
For LED red light therapy devices, continuous light using clinically supported wavelengths is the most effective approach. Pulsed light may benefit lasers due to heat management, but it is not necessary or recommended for LED panels. Factors such as wavelength, irradiance, and consistent use have a much greater impact on results.
At Streamshop Australia, we offer devices with adjustable frequencies, giving customers the flexibility to experiment and find the settings that work best for them. However, for most users, continuous LED exposure at the correct wavelengths is the safest and most effective way to enjoy the benefits of red light therapy, safely and naturally.