What is the "Right" Red Light Dosage

Let's be honest. Information is lacking in certain areas of the red light industry, dosing being one of them. There is significant disparity in the information provided by manufacturers and sellers related to their power intensity, which directly impacts the output and related dosing calculation. Even as a Certified Light Therapist, I see conflicting information among practitioners in this area.

As the market is expanding, there are a growing number of devices to choose from at varying price points. As a result, understanding the technical specifications as well as the user manual is critical. This is a huge topic and more than we can cover in a single blog, but we are going to chat more about choosing the right red light therapy device based upon your goals, following proper distance protocols, and finally, understanding dosing guidelines. Keep in mind we will be focusing on LED panels in this discussion, such as the Light Therapy Resource panels.

Choosing the Right Red Light Therapy Device:
I won't lie, dosing is not a simple topic. The right dosing (for you) is a deep, complex and rather individual topic. There are a lot of factors to consider when figuring out the proper red light dosage for you. From the intensity of your light to your individual goals and time commitment, there is a lot to consider. Here are some key factors to keep in mind when selecting a device:

1. Understanding Wavelengths:
Different wavelengths of red light have varying effects on the body. For example, 630nm and 660nm are commonly used to improve skin health, reduced inflammation, and enhanced cellular function, but don't penetrate a deeply. Whereas, for example, wavelengths of near-infrared light measuring 830nm and 850nm are commonly used for deeper bone, tissue, and muscle issues and chronic concerns. Selecting a device that offers both red and infrared light wavelengths is the best option, allowing you to choose between wavelength options based upon the issue you are treating.

2. Power and Intensity:
The power output and intensity of the red light therapy device plays a crucial role in its effectiveness. Higher power outputs generally offer deeper penetration and potentially better results, but only to a certain point and only if used correctly. Consider your intended treatment area and desired outcomes when choosing the power and intensity levels of your device. Most studies show the benefits of red and near-infrared light therapy at light outputs of 20-200 mW/cm2. But you also must take distance into account. Power density is a measurement of how concentrated the light is at a given point. The further away you are from your device, the less output you receive and therefore, you will need to adjust the duration of the session accordingly.

So how is power density measured? The most typical and inexpensive method used by the industry is a laser or solar power meter. I will be honest, this is not the most accurate method, but it is used the most by the industry and therefore provides a basis for comparison across brands and manufacturers. 3rd party testing is ideal, but typically quite costly which means you will pay more as the consumer.

As shown above, using a ruler, you can measure the power density at different distances. The ruler plays a crucial role in this exercise because you are measuring the power density at a particular distance in order to determine the dosage. For example, when you see a manufacturer specification stating “100 mW/cm2 at 6 inches,” this is what they are referring to. With a laser solar meter, you have the ability to differentiate between each wavelength you are using as different wavelengths will have different biological effects at different depths of penetration.

3. Targeted vs. Full-Body Treatment:
Decide whether you require a targeted or full-body treatment approach. It’s important to note that even if a device is powerful enough to create beneficial effects, it may still be too small for the targeted body area. If you want to treat large areas of your body, things get extremely inefficient and time-consuming. Decide what you want out of red light therapy and choose accordingly. For targeted treatments, our Handheld Torch would be ideal and if you’re going to treat larger areas of your body, our Tabletop device is a great option!

Proper Distance Protocols for Using Your Device:
Maintaining the correct distance between the red light therapy panel and your body is vital for optimal results. The closer you are to the light the larger the potency of the light dose and moving further away dramatically reduces the dose. However, closer is not always better – we recommend standing 6 inches away from the Light Therapy Resource panels to minimize exposure to EMFs (electromagnetic fields). It is recommended to follow the manufacturer's guidelines regarding the optimal distance for your specific device.

Dosing Guidelines:
To achieve the desired therapeutic results, it is important to follow appropriate dosing guidelines for your specific issue. The dose is telling you how long that power density was applied. A higher light intensity means less application time is required. Most research indicates that an ideal dose is between 2J/cm² and 60J/cm². But it depends on whether you are treating superficial or deeper tissue issues like muscles, tissue and organs. Here are a few key considerations: 

1. Understanding Treatment Duration:
The duration of each red light therapy session depends on your treatment goals. For skin rejuvenation, pain relief, or muscle recovery, sessions usually range from a few minutes to 20 minutes. The specific condition being treated and the device's power output may influence the duration.

2. Consistency and Frequency of Sessions:
Consistency is key in red light therapy. Start with a frequency of 2-3 sessions per week and gradually increase as needed. Depending upon your goals, you may benefit from daily sessions or fewer sessions per week. Monitor your progress and adjust accordingly. The applied energy is different for everyone, and research suggests everything between 2 sessions per week to 14 sessions per week. We recommend once a day to and gradually increase to once daily for the rest of your life to experience long term results!

3. Monitor your Progress:
Regularly assess your progress and make adjustments when necessary. Note any improvements or changes in your condition. If needed, increase or decrease the dosage based on your body's response to the therapy.

The most common formula for calcuating dosage is as follow:

Dose (in J/cm²) = Power Density (in mW/cm²) x Time (in seconds) x 0.001

As mentioned earlier, the distance of the light source is crucially important here, as it determines the light power density hitting the skin. For example, using the device at 10″ inches instead of 6″ inches increases the application time but simultaneously covers a larger skin area. Of course, you can use it from further away, just be sure to compensate by increasing application time. Another important factor in the correct dosage is knowing how long to apply the light:

Time = Dose ÷ (Power density x 0.001) Time in seconds, dose in J/cm² and power density in mW/cm².

For superficial areas (skin): This means that the used light will target a more superficial surface, one that is near the skin surface. Red light (660nm) is ideal here. You can generally stand further away for an optimal dose of roughly 3-15J (this is somewhere between 1-3 minutes at 6″ distance using the Light Therapy Resource Tabletop Panel). Note that the further away you stand from your device, the longer you’ll have to adjust the treatment time (18″ inches require at least 8 minutes; 24″ inches around 12 minutes).

For deep tissue use: Near-infrared light (850nm) is ideal; deeper tissues such as muscles, tendons, ligaments, bones, glands, and organs are targeted directly. For deeper light penetration, you should keep the device closer to your body (the recommended 6") and focus on higher output in order to achieve a higher overall dose in order to deliver adequate therapeutic doses to the deeper tissues. Generally, you want higher-powered devices with higher doses to penetrate deeper and through the skull (for example, when targeting the brain). You should stand closer for an optimal dose of 10-60J (somewhere between 5-10 minutes at 6″ distance).

We recommend that you limit the total treatment dose for all areas of the body to no more than roughly 80J per day until you determine your tolerance level. Assuming the light is 6″ away from your body, that means no more than about 40 minutes of total session time using the Light Therapy Resource panels on your body.

Ready to start your red light therapy journey today? All Light Therapy Resource purchases include access to our exclusive customer site, featuring handy dosage calculators, access to thousands of research papers on red light therapy, updated user manuals, tips and best practices, customer support, and more so visit our website today! Thank you for supporting our woman owned company based out of sunny California!