Systemic Effects of Red Light Therapy
For over 40 years, red and near infrared light has been studied and proven to help reduce pain and inflammation, promote healing, and prevent tissue damage, among other things. Today it is well understood that visible and nonvisible light can have a significant biological effect on the human body, leading to a wide range of potential benefits. In this article, we explain the process of how this therapy works and why such a variety of benefits are possible.
Did You Know?
While red light therapy, also referred to as Photobiomodulation (PBM), was first introduced using light sources such as lasers, LED lamps have since been introduced and found to be just as effective. Interested in the history and origins of red light therapy? You can find more here.
As mentioned, lasers and LED lamps are both recognized as valid methods in delivering PBM. While lasers are traditionally ideal for localized treatments that require higher output intensity, LED lamps can provide a larger application while still providing treatment to a localized area of the body. Regardless of the method of delivery, red and near infrared light triggers the same mechanism of action.
Let’s Get Technical
The theory and principle that visible and nonvisible light has a biological effect on humans is founded under the first law of photobiology which states that for photons of light to have effect they must be absorbed by an electronic absorption band belonging to some molecular photoacceptor.  Human cells contain an enzyme called cytochrome c oxidase (CcO) that is believed to be a photoacceptor for red and near infrared light, this being the most understood mechanism. Cytochrome c oxidase absorbs photons of red and near infrared light which helps in the cells overall process in creating Adenosine triphosphate (ATP) efficiently.  ATP is energy the body uses to function. You can read more about ATP here.
When red and near infrared wavelengths are absorbed through the skin, our cells' potential to produce energy increases. Picture a solar panel and how the internal components convert light energy into usable electricity. Our bodies are designed to use healthy light in a similar way.
As red and near infrared light continues to be studied for its use in treating specific medical conditions, the current use may be best understood as a general wellness tool to help promote healthy cellular function. Along with optimizing cellular function, circulation throughout the body can be greatly improved by the use of red and near infrared light. Good circulation is key for maintaining optimal health, ensuring that blood and oxygen continuously flow throughout the body, giving every organ a greater chance to function properly.
Other benefits from use can include relief from minor pain and aches in muscles and joints, improvements in skin health, sleep, mental acuity, wound healing and many others. Red and near infrared also helps reduce oxidative stress in our cells, so much so that even a damaged cell has the potential to be restored.
The Systemic Effect
Red and near infrared light may be best understood as a mechanism to produce positive systemic effects in the body.
Although clinically studied for a wide range of potential benefits, as the human body is very complex, it is hard to predict how PBM will work for each individual. Factors like skin types and others like reflection loss, may result in these differences. Additionally, treatment parameters for specific medical conditions remain unclear, as these parameters range from wavelength selection, fluence rate, power density, pulse structure, timing, and treatment lengths. Due to these factors, red and near infrared light remains somewhat controversial in the medical community and the full potential is still not completely understood among researchers.
Merriam Webster defines the word systemic as affecting the body in a general way.  This may be the best way to understand the wide range of benefits capable from the use of red and near infrared light and help guide the treatment parameters that are so complex.
Other sources of non-visible light, like ultraviolet (UV) light, can also have systemic effects on the body. By exposing only parts of our skin to sunlight, 7-dehydrocholesterol in the skin absorbs the UVB light and is converted to previtamin D3, which in turn isomerizes into vitamin D3 and is used by the entire body.  The systemic effects from red and near infrared light are similar, as the area receiving the light may impact other areas throughout the body. This is thought to be a result of soluble mediators such as endorphins and serotonin being released and from the recent discovery of Mitochondria free-floating throughout the bloodstream, which is further enhanced with the use of red and near infrared light. These theories support the idea of localized treatments being beneficial while also leading to benefits in other locations in the body.  
At Joovv, we believe that red and near infrared light impacts every user differently. Based on the science, we believe the benefits from use are best understood systemically and for this reason we provide generalized treatment guidelines. Even though each one of us is capable of absorbing red and infrared light, our body is the ultimate decision maker on how the light will be used. This is also one of the reasons why we believe full-body treatments are key. The more of your body you can expose per treatment, the greater the chance for it to respond to the light. Although we feel full-body treatments are optimal, using a small or moderate size device like the Joovv Go, Mini, or Solo can also be very effective.
However, like all things there is a limit to use and red and near infrared light is not exempt from this. From research we know that there is a period when maximum absorption has been achieved and continued use becomes no longer beneficial. In PBM this limit is described as the biphasic dose response, which is defined as;
“A “biphasic” curve can be used to illustrate the expected dose response to light at a subcellular, cellular, tissue or clinical level. It suggests that if insufficient energy is applied there will be no response (because the minimum threshold has not been achieved), if more energy is applied then a threshold is crossed and biostimulation is achieved, but when too much energy is applied then the stimulation disappears and is replaced by bio inhibition instead.” 
For this very reason, treatment distance and time are important to follow. Each Joovv treatment guideline is device specific and was developed to align with the biphasic response curve. To access your devices guidelines click on the link below.
In summary, we hope you walk away understanding how the use of red and near infrared light can lead to overall systemic effects throughout the body, resulting in a wide range of health benefits. We recommend following our device specific treatment guidelines to make sure you’re getting the most out of each session.
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