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What is it and should you give it a try?
Photobiomodulation might sound a bit sci-fi, but here’s what the science says.
Red light therapy, also known as photobiomodulation (PBM) is a non-invasive treatment that uses low-level light in the red (660nm) and 850nm invisible near-infrared (NIR) spectrum. This therapy has been studied for its benefits on a wide range of health conditions including improving tissue healing, reducing pain and unwanted inflammation, and enhancing cognitive function. Shining red light on parts of your body sounds a bit sci-fi! But, before you click away, let’s keep an open mind. This article will cover the science of PBM, how it works, what it treats and why it might just be what you need right now.
How does it work?
Red light penetrates the top layer of the skin and the longer infrared light penetrates several centimetres below the surface of our skin reaching our internal organs and tissues. The light should be around 3 inches away from the skin and a session on the affected area is usually between 10-20 minutes, 1 time per day.
The benefits are thought to be down to several different molecular pathways. With an evolving field of science such as this, it’s important to state that we haven’t got the mechanism of action fully worked out yet. Here is what we know so far...
PBM stimulates the production of adenosine triphosphate (ATP) in the mitochondria of cells. ATP is the primary energy source for cells, and increased ATP production can lead to improved cellular function and metabolism. This increase in mitochondrial activity also comes with a downside because this increased mitochondrial activity consequently leads to an increase in the production of reactive oxygen species (ROS). ROS have the potential to cause oxidative stress. But here is the cool thing - when ROS react with a molecule called serotonin, which is produced by the mitochondria, it results in sub-cellular melatonin production. Melatonin is a hormone that is primarily produced by the pineal gland in the brain. It plays a key role in regulating the sleep-wake cycle and has antioxidant and anti-inflammatory properties. However, recent research has shown that melatonin is also produced in the mitochondria of our cells, known as sub-cellular melatonin. Unlike sleepy pineal melatonin, this actually happens when we are out in the infrared light produced by the sun, not when it gets dark. The evolutionary origins of this are hypothesised to be down to our need for the antioxidant effects of melatonin at the mitochondria of our cells during the day. Sub-cellular melatonin produced in the mitochondria has been shown to have several benefits. It can scavenge ROS and protect cells from oxidative stress, tissue damage and inflammation.
Exposure to infrared light via PBM can increase the production of this sub-cellular melatonin. Mitochondrial sub-cellular melatonin production is therefore an important mechanism by which PBM exerts its therapeutic effects.
Other proposed mechanisms include:
Activate cellular signaling pathways, such as the PI3K/Akt and MAPK/ERK pathways, which can promote cell survival and proliferation.
Reduce inflammation by inhibiting the production of pro-inflammatory cytokines and promoting the release of anti-inflammatory cytokines.
Promote the formation of new blood vessels, which can improve blood flow to damaged tissues and promote healing.
Increase the release of nitric oxide (NO) from cells. NO is a signalling molecule that plays a role in vasodilation, immune function, and neurotransmission, among other functions.
Promote DNA repair in cells, which can help to prevent mutations and cellular damage that can lead to disease.
Modulate neural activity by promoting the release of neurotransmitters and improving the function of neural mitochondria. This can be beneficial for conditions such as neuropathy, stroke, and traumatic brain injury.
Some of the conditions that PBM has been shown to be useful for include:
Pain Management: One of the most studied applications of PBM is pain management. Numerous clinical trials have shown that PBM can effectively reduce pain and inflammation in various conditions, including osteoarthritis, rheumatoid arthritis, low back pain, and fibromyalgia. PBM has also been shown to have a positive effect on nerve function, which can be beneficial in conditions such as neuropathy.
Wound Healing: PBM has been shown to accelerate wound healing and reduce scarring. It works by increasing blood flow to the affected area, promoting the formation of new blood vessels, and stimulating the production of collagen, which is essential for tissue repair.
Skin Health: PBM has been shown to have a positive effect on skin health, including reducing the appearance of wrinkles and fine lines, improving skin tone and texture, and promoting the healing of acne and other skin conditions.
Sports Performance and Recovery: PBM has been shown to enhance athletic performance and speed up recovery from sports-related injuries. It can improve muscle strength, endurance, and recovery time, as well as reduce muscle soreness and inflammation.
Neurological Conditions: PBM has been studied for its potential use in treating a range of neurological conditions, including traumatic brain injury, stroke, and Parkinson's disease. It has been shown to promote nerve regeneration, reduce inflammation, and improve cognitive function.
Oral Health: PBM has been shown to have a positive effect on oral health, including reducing pain and inflammation associated with periodontal disease and promoting the healing of oral wounds.
A special word on infections. A recent study demonstrated the utility of this treatment for covid infection. In this study, they investigated the impact of PBM as a treatment for hospitalised patients with COVID-19. Their hypothesis was that PBM treatment could reduce oxidative stress in COVID-19 patients, helping them recover quicker than conventional treatment alone. Why do infections like COVID-19 cause oxidative stress? Oxidative stress occurs downstream of the inflammation elicited by the immune system to deal with the infection. Oxidative stress can also occur if the microbe, like SARS-CoV-2 hijacks the renin-angiotensin system (RAS). To understand this we need to know a little more about the RAS system:
Angiotensin-II (a pro-oxidant) is converted to angiotensin-17 (an antioxidant). This occurs via an enzyme called ACE2
ACE2 is also the receptor for SARS-CoV-2.
SARS-CoV-2 infection can shut down ACE2 so you end up with a build-up of angiotensin-II (the pro-oxidant) and a reduction in angiotensin-17 (the anti-oxidant).
This adds to the oxidative stress of the infection (in addition to the oxidative stress caused by the inflammation directed against the virus itself).
This study was a randomised controlled trial (this is an important aspect of this study as it helps to eliminate many confounders). It is also important to note that it was only performed on a small number of participants (30 patients). They employed a PBM device that emitted near-infrared light (940 nm wavelength) directly onto the chests of participants to deliver 15mins of PBM (or placebo). Participants were randomised and matched for BMI and age. The PBM treatment group did better than the controls across a number of parameters. The data were powerful enough to see a significant benefit in recovery even with the small number of participants. Notably, treatment resulted, on average, 4 days less in the hospital. Importantly PBM treatment had no reported side effects or complications. This suggests it could be a safe, non-pharmacological, painless and low-cost modality as an adjunct to conventional therapy. I hope this study stimulates further research in this area.
In summary
PBM is a non-invasive therapy that uses low-level light to modulate cellular function and is shaping up to be a promising therapy with a wide range of potential health benefits. The scientific literature and evidence supporting the use of PBM for health are growing. While more research is needed to fully understand its mechanisms of action and potential applications, PBM has been shown to be a safe, non-invasive, and effective treatment option for a range of health conditions.
Should you try PBM?
So there you have it, a comprehensive look at PBM. While PBM is becoming more common in clinical settings, it is also possible to use it at home. I have been using PBM for many years and I have found it helpful to keep on hand for so many aspects of my health such as targeted injuries, skin issues and infections. It also Many of us have jobs or life circumstances that keep us indoors for large parts of the day so we do not benefit from the red and infrared produced by the sun. Home PBM devices would also be useful (but not a replacement for getting outside) for this situation.
Make it a ritual
The device I currently use at home is the Bon Charge Mini Device. I tend to do 10-20mins every day, at any time of day that works for my schedule. This is NOT a sponsored article. Bon Charge did not ask me to write this but as a user of their devices, they have kindly gifted readers 15% off any product with code JENNA15. The discount applies to any product. They don’t just do red light devices but a bunch of different science-backed wellness products to optimise well-being and recovery. Enjoy and tag me on Instagram if you try PBM after reading this!