Red light therapy, also known as low-level light therapy (LLLT), is a non-invasive treatment that uses red and near-infrared light to improve various aspects of health and wellness. It works by exposing the skin and underlying tissues to specific wavelengths of light, which can penetrate deeply and trigger multiple cellular responses in the body, including increased cell energy production. It can be administered in various ways, including handheld devices, light panels, and full-body beds. Treatment times and frequencies may vary depending on the specific condition being applied as well as the device being used.
Although the mechanisms of red light therapy are not yet fully understood, it is believed to work by affecting cellular processes at a molecular level. More specifically, it is thought to stimulate the production of adenosine triphosphate (ATP), the energy currency of cells. An increased ATP production can help cells function more efficiently and promote healing. Red light therapy may also be implicated in another cellular process which is mitochondrial biogenesis. Mitochondria are the energy-producing organelles within cells. Red light therapy has been shown to increase the expression of genes involved in mitochondrial biogenesis, namely the production of new mitochondria, as well as stimulate the activity of the existing mitochondria. As a result, it can improve overall mitochondrial function and may thus increase energy production and cellular metabolism.
Red light therapy may also work by reducing oxidative stress and inflammation processes in the body. Particularly, it has been found to reduce oxidative stress by increasing the activity of antioxidant enzymes, such as superoxide dismutase (SOD), catalase, and glutathione. These enzymes play key roles in maintaining the body’s oxidative balance by preventing damage to cells and tissues. Along with oxidative stress, chronic inflammation is another harmful cellular process where red light therapy has been proven beneficial. More specifically, it has been shown to decrease inflammation by reducing the production of pro-inflammatory cytokines and increasing the production of anti-inflammatory cytokines.
Lastly, red light therapy is believed to exert its benefits through two additional mechanisms, being an increased blood flow to the affected area and stimulation of collagen production. Regarding circulation, it is thought to increase blood flow by stimulating vascular endothelial growth factor (VEGF), namely a protein that promotes the growth of new blood cells. This process can help deliver oxygen and nutrients to the affected tissues as well as remove waste products and toxins from the body and, as a result, promote wound healing and accelerate recovery. In this direction, red light therapy is also thought to stimulate collagen production, a protein intertwined with wound healing and tissue repair.
The proposed benefits of red light therapy stem from the mechanisms described above. Therefore, its most vital benefits revolve around recovery. More specifically, thanks to its ability to stimulate the production of VEGF and collagen, red light therapy can aid in the healing of injuries and pain relief, thereby reducing muscle fatigue and soreness, speeding up muscle recovery, and eventually increasing athletic performance. Due to its potential to modulate inflammation, its recovery properties may also expand on more serious chronic health conditions, including psoriasis and arthritis.
Another rather intriguing benefit of red light therapy is its implication on cellular health and function through its effect on ATP and mitochondria. More specifically, it has been shown to enhance mitochondrial function, leading to increased cell energy production in the form of ATP, improved metabolism, and increased ability to utilize fat as a fuel source. Enhanced fat-burning efficiency is vital for cellular health and function and is also a marker of metabolic health. The more reliant on fat a subject is the less likely it is to suffer from metabolic disease, such as obesity and diabetes.
Additional suggested benefits of red light therapy include improved sleep as well as reduced anxiety and depression. In particular, red light therapy may help improve sleep quality and duration by regulating the body’s circadian rhythm as well as improving melatonin production. It has also been found to affect anxiety and depression symptoms positively by promoting the production of the neurotransmitter serotonin.
In a nutshell, while the exact mechanisms are not fully understood, red light therapy has shown promise as a safe and effective therapy for various conditions. It can increase cellular energy production through increased ATP production, improve mitochondrial function, enhance circulation, reduce inflammation, and increase collagen production. These mechanisms work together to reduce pain and symptoms of chronic inflammatory diseases, improve wound healing and recovery, enhance fat-burning efficiency, and soothe psychological stress.
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