Let’s face it. There is a lack of knowledge on dosing and a significant discrepancy on different devices and their power intensity. Even though the market isn’t enormous (yet), there are numerous devices to choose from when starting your red-light journey, which makes specifications on technical and user-friendly information even more critical. This article will give you a first insight into how to measure the right power intensity, set an ideal treatment time for you, and ultimately get a grip on dosing your red and near-infrared light device. Please keep in mind this is a humongous topic which we will not be breaking down in only this article! Also, we’ll be focusing mainly on LED panels, such as our Luminousred devices.
Table of Contents
- In our opinion, to get the maximum out of light therapy, you need to answer three questions:
- What do you want out of red-light therapy?
- How strong would my red-light therapy device be (at various distances)?
- With our devices, the measurements are as followed:
- How long should I use my device / How do I calculate the dose?
- Get your red light buddy now
- Sources and References:
In our opinion, to get the maximum out of light therapy, you need to answer three questions:
- What do I want out of red-light therapy?
- How strong should my red-light device be (and this, at different distances)?
- How long should I use it?
This knowledge is essential, as overdoing treatments will decrease effectiveness. After all, what’s the point in that at the end of the day?
What do you want out of red-light therapy?
Research suggests numerous benefits of red-light therapy. The main ones are skin health, hormonal health, hair growth, less pain, less inflammation, cellular health, and better circulation.1, 2, 3, 4, 5, 6 Now depending on what your “goal” is, there are different treatment areas and protocols you should follow.
How strong would my red-light therapy device be (at various distances)?
Most studies show the benefits of red and near-infrared light therapy at light outputs of 20- 200mW/cm2. The keywords here are power density and distance.7, 8, 9, 10
Power density is a measurement of how concentrated the light is at a given point.
As already mentioned, the further away you stand from your device, the longer you should adjust the treatment time accordingly.
Power density is usually tested with a laser power meter.
With the help of a ruler, you can measure the power density at different distances. The ruler plays a crucial role in your red-light regime, as you want to have the right primer (power density) at the right distance to get the effect you want. You also should differentiate between each wavelength. In our Luminousred devices, you have three measurement settings: 660nm of red light, 850nm of near-infrared light, and 660+850nm combined.
With our devices, the measurements are as followed:
How long should I use my device / How do I calculate the dose?
Dose (in J/cm2) = Power Density (in mW/cm2) x Time (in seconds) x 0.001
The dose is telling you how long that power density was applied. A higher light intensity means less application time is required. The intensity is particularly important because we want to have a high-intensity device for taking advantage of the benefits of red-light therapy in as little treatment time as possible. Who would want to stand/sit in front of their light for 30 minutes rather than 10, right?
As you can now calculate what dose you are getting, you need to know what dose is effective. Most review articles and educational material tends to claim a dose in the range of 0.1J/cm² to 6J/cm² is optimal for cells, with less doing nothing and much more canceling out the benefits. The essential piece of information you need to know is that the ideal dose according to scientific studies is between 3J/cm2 – 50J/cm2. You want different doses depending on whether you’re treating superficial areas like the skin or surface wounds or deeper tissues like muscles/organs.
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 4″ 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 of red-light therapy 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/cm².11
For skin issues: 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 (somewhere between 1-4 minutes at 12″ inches distance). Note the further away you stand, the longer you’ll have to adjust the treatment time (18″ inches require at least 5 minutes; 24″ inches around 8 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. The deeper you want the light to get in, the closer to your body you want the light to be ( 6″ is ideal according to science), and the higher the overall dose you want to do, so that you deliver adequate therapeutic doses to the deeper tissues. Generally, you want higher-powered devices with higher doses here to penetrate through the skull (for example, when targeting the brain). You should stand closer for an optimal dose of 10-60J (somewhere between 2-7 minutes at 6″ inches distance).
By now, we have mentioned the difficulties with dosing multiple times. The right dosing (for you) is a deep 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 goal and optimal treatment time, there is a lot you can do wrong.
The body is three-dimensional. We calculate applied light to the surface of a specific area; there is still an unknown. 1J/cm2 can be used to differently sized skin areas (5 cm2 or 50 cm2), or through different strengths (2mw/cm2 for 500 seconds vs. 500mw/cm2 for 2 seconds), the total energy applied will be vastly different in both cases which leads to different outcomes.
Usage frequency plays a vital role. The applied energy is different for everyone, and research suggests everything between 2x/ week to 14x/week. We recommend once daily (7x/week) and doing it for the rest of your life rather than two months (research studies usually run for a shorter testing period!)
Distance from the light. Know, that the measure of power density decreases by moving further from the light source. Generally, the closer you are to the light the bigger the potency of the light dose, and moving further away dramatically reduces the dose. However, closer is not universally better – we advise staying at least 6″ inches away to minimize exposure to EMFs (electromagnetic fields).
Wavelengths of the light. Decide what you want out of red-light therapy and choose accordingly.
Claimed wattage vs. actual wattage. As already mentioned, this is a big one. The truth is that even with all calculations provided, it’s just a theory. You don’t know the actual light intensity output of the light you get until you measure it. You have to rely on exact measurements using a laser power meter, rather than calculated measurements based on theoretical wattages.
Size of the device and treatment area. It’s important to note that even if a device is powerful enough to create beneficial effects, it may still be too small as only a small area of the body is targeted. 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 model1 is ideal; if you’re going to treat your whole body (in less time), you can start building your set-up starting with the model2 and stacking up as you’d like.
For general use, we recommend having the light at a distance of 6-36″ inches away from your body. Closer distances are great for deep tissue penetration. Further distances) are good for treating surface skin issues.
For skin issues, we want between 3J-15J per area. Recommended regimes:
- 30 seconds-2.5 minutes per area (if the light is 6″ inches away)
- 1-3.5 minutes per area (if the light is 12″ away)
- 5-5 minutes per area (if the light is 18″ away)
- 2-7 minutes per area (if the light is 24″ away).
- 3-14 minutes per area (if the light is 36″ away)
For deeper issues we want around 10-40J per area. Recommended regimes:
- 2-7 minutes per area (if the light is 6″ inches away)
- 5-10 minutes per area (if the light is 12″ away)
Get a high-power light that can still deliver an effective dose from further distances. Higher power allows you to treat much larger areas of your body at once compared to lower-powered lights.
The ideal frequency of use is likely between 3-7x/week (or up to once per day). Some studies have used more and less than this, but based on our experience, we believe between 3 to 7 times per week is optimal.
Start SLOW. The pace is especially important if you are in poor health or doing it for the first time. More is NOT better; it can even lead to no effects in the worst case. Start with the lowest possible doses and slowly increase the dosage from there in subsequent sessions. Don’t forget to track your progress and adjust accordingly.
Total Treatment Dose/Time: We suggest that you limit the total treatment dose for all areas of the body to no more than roughly 120J. Assuming the light is 6″ or 12″ away from your body, that means no more than 15-20 minutes of time total with light shining onto your body.
Get your red light buddy now
Other companies use solar power meters; the issue here is an inaccurate representation of the actual measurements. We’ll do another blog post about this if you’re interested. Do you want to learn more? Let us know your thoughts in the comments . Get your Luminousred now.
Sources and References:
 Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring. MAr. 2013
 Effects of low-power light therapy on wound healing: LASER x LED*. Aug. 2014
 Effects of low-level laser therapy on pain in patients with musculoskeletal disorders: a systematic review and meta-analysis. Aug. 2017
 Influence of low-level laser therapy on the healing of human bone maxillofacial defects: A systematic review. Apr. 2017
 Mechanisms and applications of the anti-inflammatory effects of photobiomodulation. May 2017
 Luminousred Photobiomodulation research database. Powered by Vladimir Heiskanen. Jan 2020
 A Controlled Trial to Determine the Efficacy of Red and Near-Infrared Light Treatment in Patient Satisfaction, Reduction of Fine Lines, Wrinkles, Skin Roughness, and Intradermal Collagen Density Increase. Feb. 2014
 The nuts and bolts of low-level laser (light) therapy. Feb. 2012
 Power density and exposure time of He-Ne laser irradiation are more important than total energy dose in photo-biomodulation of human fibroblasts in vitro
. BIPHASIC DOSE RESPONSE IN LOW LEVEL LIGHT THERAPY. 2009