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How to use red light therapy at home

how to use red light at home

Key Points

  • Red light therapy is a cheap and effective treatment to improve your health, body, and wellbeing
  • Choosing the right wavelength is important for optimal results
    • Shorter wavelengths (red light, 650 nm) penetrate less, and are best suited for skin issues (anti-aging, eczema, acne) and superficial wounds
    • Longer wavelengths (near infrared, 850 nm) penetrate deeper into the body, and thus works better for muscle recovery, anti-inflammation, brain boost, and bone health.
    • Devices that combine both red and near infrared are usually the optimal solution to enjoy all the benefits of red light therapy.
  • Choosing the right dose of red light therapy is also crucial to optimize benefits without negative impacts
    • Doses of 1 to 10 J/cm2 are desirable for superficial targets such as skin and hair
    • Doses of 10 to 50 J/cm2 are required when the target treatment zones are deeper such as muscles, brain, and bones
    • This might mean different session durations depending on the device used
  • Red Light Therapy should be used in a consistent way from 1 to 5 times per week


Red light therapy (also known as Photobiomodulation or Led Light Therapy) is a practice that has been around for many years, but it only recently became popular as people are looking for alternative methods of treatment. For those with an interest in health and wellness, this can be an exciting discovery. We went through the detailed benefits of red light therapy and growing research around it in our previous article (11 Benefits of Red Light Therapy). However, when you’re looking to use red light therapy from home, there are some factors you need to consider before beginning the process. In this article today, we will discuss

  1. Choosing the right wavelength for your red light therapy based on your needs
  2. Choosing the optimal dose 
  3. Choosing the optimal frequency

1) The Right Wavelength

Before you buy any red light device, it’s a good idea to know what you want out of your treatments. Are you looking for a natural anti-aging solution? Do you want relief from joint pain or stiffness? Or are you aiming for a serious sports performance boost? The truth is, depending on your goals, different wavelengths and durations will serve them best. 

The choice of wavelength affects tissue penetration. Longer wavelengths (near infrared, 780 to 950 nm) are recommended for treating deeper tissues, whereas shorter wavelengths (red, 600 to 700 nm) are preferred for treating superficial tissue. Near-infrared light penetrates 2 mm before losing 37 percent of its intensity, whereas red wavelengths penetrate 0.5 to 1 mm. 

Red light on the other side is better suited for treating skin issues (anti-aging, acne, eczema) and superficial wounds. As near infrared penetrates more through the skin compared to red, it works much better for bone repair, for treating internal inflammation, and for boosting muscle recovery and brain chemistry. In addition, many studies show that the effects of near infrared last longer.

Wavelengths between 700 and 770 nm seem to be ineffective, while wavelengths around 660 nm (red) and 850 nm (near infrared) seem to achieve the better result. This is most likely linked to the fact that cytochromes – which are responsible for the photochemical effects of red light therapy in our body – have the highest absorption of light around those wavelengths.

red light therapy and near infrared light therapy spectrum absorption by cells

For optimal results, it is often better to combine both red and near infrared light within the same device.

2) The Right Dose

There is clear consensus across scientists that red light therapy complies with the Arndt–Schultz law which states that “For every substance, small doses stimulate, moderate doses inhibit, and large doses kill.”

What this means is that there is an optimal dose of red light therapy to get the best possible benefits, and over exposure beyond that dose can be counterproductive. 

Here, you might ask what we exactly mean by red light therapy dose. Well, here again, there is broad consensus that dose here means the quantity of photons that your body receives (or fluence). This is expressed in Joules / cm2, and is a function of the flow of photons per surface (expressed in Watts / cm2) and the exposure time (expressed in seconds or minute). 

There is an important concept, called the Roscoe–Bunsen law of reciprocity that applies here. This concept states that the most important parameter in red light therapy is the total quantity of photons absorbed by the target cells. This is expressed in Joules / cm2, and is a function of the flow of photons per surface (expressed in Watts / cm2) and the exposure time (expressed in seconds or minute).  It is not important how quickly or how slowly these photons are delivered. For instance, 100mW/cm2 applied for 60 s for a dose of 6 J/cm2 will have the same effect as applying 1 W/cm2 for 6 s (6 J/cm2) or 6W/cm2 for 1 s (6 J/cm2) using the same spot size.

red light therapy dose

Now what dose should we target? Numerous studies suggest doses ranging from 1 to 10 J/cm2 produce the desired results for superficial targets (like your skin), while deeper targets (like muscles and bones) require doses from 10 to 50 J/cm2.

To illustrate this let’s take an example:

  • For an average intensity infrared, at a distance of 24 inches, the optimal session duration should be between 10 and 30 minutes. 
  • For a more powerful infrared, only 2 to 6 min sessions are needed to get the same results.
red light therapy dosing for infracare and infralight

3) The Right Frequency

In order to get sustained benefits from red light therapy – it is important to fully embed red light therapy in your wellbeing routine. However, as stated above, more is not always better.

For optimal results, red light therapy should be used from 1 to 5 times a week. 


Red light therapy is a cheap and effective way to improve your health and wellbeing on so many dimensions. It has the advantages of being an accessible treatment that can be done from the comfort of your home using high grade home devices (20% OFF with code 360UPGRADE). But it is important to use the right wavelength and the optimal dose to reap all of the exciting benefits. Now test with your red light device starting with short sessions, and increasing session duration and frequency until you start feeling a good level of response from your body – and follow our guidance above to avoid overexposure. 


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