How Much Red Light Therapy Do I Need?

When it comes to red light therapy recommendations, a common question I hear as a Certified Light Therapist is...how much time do I need to spend under the light? What dosage do I need? I wish I could say there was a super easy answer, but there isn't. Our bodies are unique, they respond differently to red light therapy, our goals are different, we are using different devices and applications, there are just so many variables. Compound that with the fact that there are ton of different devices to choose from on the market.

However, we have compiled this list with a few factors to consider as you explore red light therapy treatments. 

1. The depth of the issue: it takes different amounts of light and often different wavelengths to affect the skin versus penetrating bone or deep muscles. Alternately, activating acupuncture (aka photopuncture) points can take only a few seconds.
2. The speed of delivery (how much light is coming out of your device divided by the area that is being illuminated)…faster is not always better.
3. How far from the body the light source is located. For every inch of distance you lose about 50% of the photons and therefore you need to use your device for a longer time.
4. Whether the lymph system is already open and able to handle the increased circulation stimulated by the photobiomodulation.
5. How healthy you are. The sicker someone is, the slower you need to proceed. Too much light in a single session could trigger a healing crisis; headaches, body aches, etc.

Most references and studies regard an effective dose for a single red light therapy session to be between 3 to 80 Joules/cm² for the treatment area. It's a huge range, I know. But it is a starting point. Now, a Joule is a measure of energy delivered in one second. The output of most red light therapy devices is measured in milliwatts (mW). 1000 mW in one second is equivalent to 1 Joule (J). So with the right formula, we can calculate the amount of time we need to spend under the light.

Let's take the Light Therapy Resource Tabletop panel for example. The output is 125 mW/cm² at 6", which is the distance I would use it at to avoid EMF exposure. In order to determine the amount of time I need for my session, as mentioned above, I need to determine if I am focusing on deeper penetration into muscle and bone or if I have skin and surface level concerns. Let's say I hurt my ankle and am looking for relief. I would shoot for a higher dosage of Joules to penetrate deeper, so let's go with 60 Joules. This is how we calculate the amount of time we need to spend under the Light Therapy Resource Premium Tabletop Panel: