Red light therapy, which is also known as low-level light therapy (LLLT) and photobiomodulation, offers exciting potential as a treatment for brain health, including age-related decline, traumatic brain injuries, and stroke. Below, we’ll discuss the effects of red light therapy on brain health and how this promising treatment could help people restore normal brain function.
Note: Shop clinical-grade light therapy devices in the Platinum Therapy Lights store.
How Does Red Light Work on the Brain?
Red light therapy involves using devices fitted with LED bulbs to apply a narrow spectrum of light to bare skin. Specifically, this is a range of light wavelengths, measured in nanometers (nm), that includes red (630 to 660 nm) and near-infrared (810 to 850 nm).
These wavelengths have been widely studied and confirmed to have a powerful stimulating effect on the human body.
Based on encouraging clinical trials specific to the effects of red light on brain health, along with encouraging anecdotal reports, researchers believe red light may be useful in improving brain cell metabolism and reducing inflammation.
These two effects are the keys to potentially enhancing overall brain function, supporting the treatment of psychiatric disorders, and accelerating healing from stroke or injury.
Just as importantly, red and particularly near-infrared (NIR) wavelengths are long enough to penetrate human tissue – and even bone – which can make red light therapy a viable treatment for brain health.
Can Red Light Therapy Absorb into Brain Tissue?
The short answer is yes.
This illustration can help you visualize how deep red and NIR light absorbs into the body:
In one published study, the authors found that the visible red wavelengths from 610 nm to 670 nm can absorb into the skin to a maximum depth of between 4–5 mm, which is the subcutaneous layer of tissue just below the dermis.
The same study shows that near-infrared light (810 nm, 830 nm, 850 nm) can absorb into the tissue to a maximum depth somewhat greater than 5 mm, or a little over 2 inches.
The human skull, particularly in the forehead, is roughly 6.8 to 7.7 mm thick, which is about .275 inches. So, infrared and NIR light wavelengths can easily pass through the skull and the meninges (a three-layer-deep type of tissue that covers and protects the brain) and the cerebrospinal fluid, before absorbing into the brain tissue.
What about longer infrared light wavelengths; are they good for brain health? Not really – as surprising as it might seem. While mid-infrared light waves can penetrate deeper into brain tissue, infrared light over 1,000 nm is no longer perceived as light; rather, the body perceives it as heat, which does not have the same therapeutic value as light.
How Does the Light Get to the Brain?
Most red light therapy treatments are given through the forehead, meaning the light absorbs into the cerebrum. It is also possible to target other regions in the brain, although absorption depth will be shallower in individuals with a thick head of hair.
Some researchers have suggested that red light could be delivered intranasally (through the nose) to enhance absorption into brain tissue.
When an LED device is used, someone receiving red light therapy could potentially alternate between transcranial (through the forehead), intracranial (through the ear or just behind the ear where there is little or no hair), intranasal, and oral (through the mouth) treatments to enhance absorption and affect different parts of the brain.
How Does Red Light Affect the Brain?
The therapeutic benefits of red light therapy occur at the cellular level. So, unlike medications or other remedies that simply mask symptoms, red light works from the inside out to promote health – including brain health.
There are several mechanisms at play here; together, they support the body in ensuring brain health.
Neuroprotection for Parkinson’s, Alzheimer’s, and More
Of great interest are studies that observe the neuroprotective effects of red light. This could mean huge advances in the treatment of degenerative brain disorders such as Alzheimer’s and Parkinson’s.
A 2007 study by researchers from Israel focused on the effects of red light therapy on patients who had suffered an ischemic stroke, which is the most common type of stroke. The study found that 810 nm near-infrared light provided neuroprotective benefits (protecting neurons from damage) and improved recovery among patients whose stroke was moderate to severe.
Five days after the stroke, patients in the treatment group showed significant improvement, compared to those who were not treated with NIR light therapy (control group). Ninety days post-stroke, 70 percent of the treatment group had a successful outcome, compared with just 51 percent of the control group.
A more recent study, conducted in 2019 by world-renowned photobiomodulation expert Michael R. Hamblin, focused on Alzheimer’s disease. Hamblin’s study revealed that red light helps with neuroprotection, which safeguards patients’ survival and longevity and slows abnormal cell death due to inflammation.
During a 2018 review, Iranian researchers analyzed preclinical and clinical evidence regarding the efficacy of near-infrared light treatment of the brain. The review confirmed the neuroprotective effect of NIR wavelengths.
Enhanced Brain Cell (Neuronal) Functioning
Another of Hamblin’s findings during his 2019 study was that a primary benefit of red light therapy is improved metabolic cell functioning.
When red and NIR light photons are absorbed by the body, they stimulate metabolic energy production in the mitochondria. Sometimes called the cells’ “batteries,” mitochondria are the energy-producing centers of cells, including brain cells (neurons) and even stem cells that are produced in the bone marrow.
Red light therapy stimulates mitochondria to produce more adenosine triphosphate (ATP), the primary fuel for most cells. When cells are energized, they function more efficiently.
By contrast, a condition called mitochondrial dysfunction occurs when something interferes with mitochondria’s ability to produce ATP. Culprits often include oxidative stress and inflammation, which often go hand-in-hand.
In this 2014 article, Case Western University researchers demonstrated that mitochondrial dysfunction is a direct cause of Alzheimer’s disease. Similar studies, including this 2018 study by researchers from the University of Sydney in Sydney, Australia, confirm the connection between mitochondrial dysfunction and Parkinson’s disease.
Improved Cerebral Blood Flow
Wherever there is damage to cells, whether they are skin cells or neurons, promoting increased blood flow is a way to accelerate and support healing. In his 2019 article, Hamblin states that red light stimulates cerebral blood flow and increases brain oxygenation in Alzheimer's patients.
This could potentially help people with other neurodegenerative disorders and traumatic brain injury (TBI) recover from a condition known as neurovascular dysfunction, which can result in low brain oxygenation and slow healing.
These findings have been confirmed by other studies, including this one from 2018 that focused on the after-effects of traumatic injury to the brain in war veterans.
Reduced Inflammation and Oxidative Stress
Although acute inflammation is a product of the immune system and a necessary part of healing, chronic inflammation in the brain can have serious negative effects. Chronic inflammation is linked to many neurodegenerative diseases and persistent psychological disorders.
Many researchers point to the anti-inflammatory effects of red light therapy. In this 2017 paper, Hamblin details the mechanisms by which red light therapy reduces inflammation.
In a process called neurogenesis, red light has been shown to stimulate the regrowth of neurons, which is key to healing from injury or neuronal degeneration.
The authors of this 2016 review cite several promising animal studies that led to clinical trials. This body of research showed that treatment with near-infrared light therapy could be safe and effective for people suffering from acute and chronic traumatic brain injury, as well as neurodegenerative disorders.
A 2017 study co-authored by Hamblin and researcher Madison Hennessy found that red light therapy stimulates synaptogenesis, which is the formation of synapses between neurons. This, in turn, influences the brain’s neuroplasticity, or natural ability to reorganize itself by forming new neural connections.
This could be especially helpful in cases of TBI where cognitive functions have been impaired – which suggests that red light therapy could potentially be used as part of a comprehensive treatment program that includes behavioral and/or cognitive therapy.
Increased Stem Cell Production
Red light stimulates the production of stem cells, which are the body’s master cells. These cells reside in an inactive state in bones and bone marrow throughout the body, ready to be mobilized as needed, usually in response to injury or other cases of cell death or dysfunction.
The Benefits of Red Light Therapy on Brain Health
Findings across a number of studies show that NIR therapy shows incredible promise in enhancing cognitive functioning and supporting healing from TBI, stroke, or neurodegenerative disorders.
In particular, wavelengths of 810 nm to 850 nm appear to offer the most scientifically validated neurological benefits because of their deep absorption into brain tissue.
Improved Recovery from Stroke
According to the CDC, each year more than 795,000 people in the United States suffer a stroke. Sometimes called “brain attacks,” strokes can cause lasting brain damage and long-term disability and loss of key brain functions. Nearly 90 percent of strokes are ischemic strokes, in which blood flow to the brain is blocked.
In 2007, researchers from Israel conducted a clinical trial with patients who had suffered an ischemic stroke. Transcranial application of 810 nm light was applied to the heads of the patients. Significant and lasting improvements were noted even after only one treatment, and results were still evident 90 days later.
Strokes often affect basic motor functions. Some patients experience spasticity, which can cause pain and weakness.
In a 2016 study, researchers from Brazil treated stroke patients with red light therapy, and patients experienced reduced pain and increased time to onset of muscle fatigue. These findings suggest that red light therapy may contribute to increased (and normal) recruitment of muscle fibers and reduction of pain.
In a 2016 article titled, “Shining Light on the Head: Photobiomodulation for Brain Disorders,” Hamblin cites research that’s had notable results in treating stroke:
- Animal studies: After treatment with 660 nm red light, nitric oxide activity was suppressed; after treatment with 808 nm NIR light, neurogenesis began within 24 hours of stroke, and researchers observed improvements in behavioral performance and neurological function;
- Human clinical trials: Twenty patients aged 40 to 85 who had suffered from an ischemic stroke showed improvement in neurological deficits after treatment with 810 nm NIR light.
Accelerated Recovery from Traumatic Brain Injury
According to the CDC, each year emergency rooms throughout the United States see more than 2.5 million patients suffering from concussions and other types of traumatic brain injury.
Symptoms can include amnesia (no memory of how the injury occurred), headaches, slurred speech, confusion, anxiety, severe depression, memory lapses, lack of impulse control, sleep disturbances, and suicidal thoughts.
One type of brain injury is chronic traumatic encephalopathy (CTE), which is a progressive neurodegenerative disease attributed to repeated head trauma. Whether the head trauma is severe or a mild TBI, the long-term effects often vary.
CTE has been closely connected to contact sports such as football, boxing, rugby, soccer, and hockey, and may develop long after the head trauma occurred. CTE may also affect military veterans who have suffered a blast injury to the head.
Moderate brain injuries may result in noticeable and immediate problems, and complications are often expected after a moderate traumatic brain injury.
However, a mild TBI can be difficult to treat since some symptoms may appear right away and others can take weeks, months, or even years to manifest. While long-term effects are often associated with more serious injuries, even a mild traumatic brain injury can become a chronic lifelong problem long after the person was injured.
For example, neuroinflammation is thought to be a link between TBI and the subsequent development of neurodegenerative diseases such as Alzheimer's disease.
NIR light therapy shows great promise as a healing treatment modality for TBI and CTE. But real effectiveness requires the use of equipment with enough energy to achieve the depth of penetration needed to affect brain tissue that is most often damaged during injuries.
In his 2016 article, “Shining Light on the Head: Photobiomodulation for Brain Disorders,” Hamblin writes that light therapy with 660 nm and 810 nm wavelengths is the most effective at promoting significant improvements in cognitive function after a brain injury.
By increasing cellular energy (stimulation of ATP production in the mitochondria), as well as increasing cerebral blood flow, NIR wavelengths can improve the subnormal cellular activity of injured brain tissue following mild TBI.
As confirmed by this pilot study, 810 nm NIR light has been shown in animal studies to be particularly effective in promoting recovery from traumatic brain injury and reducing long-term neurological damage.
Improvement in Psychiatric Disorders
It can be challenging for patients who suffer from psychiatric conditions to find treatments that help. Prescription drugs, which are commonly prescribed for these conditions, don’t necessarily relieve symptoms and often carry unwanted side effects.
Bright light has long been used to treat seasonal affective disorder (SAD) and other psychological disorders. However, the use of red light appears to be the most beneficial overall, with no known side effects.
For instance, during a 2009 study on the psychological effects of near-infrared light on major depression and anxiety, patients suffering from major depression and anxiety were treated with 810 nm wavelengths applied to the forehead. This treatment proved to be beneficial with no adverse side effects.
While still experimental, this 2016 study found that the use of red light therapy for brain disorders is promising.
A 2018 study found that an eight-week treatment period using red and NIR light therapy showed great potential for treating depressive disorders.
NIR light therapy was successful in treating depression linked to a TBI, according to this 2017 study of 39 patients who were treated for severe depression following TBI. After treatment with NIR light, most patients had significant improvement in depression symptoms and remained in remission for more than four years.
Depression is linked to sleep disorders, and red light therapy has been shown to improve sleep. Elite female basketball players in China were treated with red light during a 2012 study on the effects of red light on sleep and subsequent athletic performance. Participants showed improvement in sleep and an increase in natural melatonin, which aids with sleep and is notably deficient in people suffering from depression.
In one study on the effects of red light on depression and anxiety, participants treated with NIR light therapy reported improved sleep, improvements in cognitive performance, and fewer PTSD symptoms. One participant reported a restored ability to perform actions such as writing checks and paying bills for the first time since a motor vehicle accident five years before.
Slowed or Reversed Cognitive Decline
Cognitive decline is a major concern after a traumatic brain injury During a 2014 study on patients with TBI, researchers from Massachusetts found improvements in cognitive function after red/NIR treatments in these patients. Improvements were seen in executive function, verbal learning, sleep, and when present, PTSD symptoms.
A 2014 study published in the Journal of Neurotrauma focused on brain damage in Gulf War veterans. The researchers found that the veterans benefited from a treatment regimen of red light therapy with both red and NIR light, combined with cognitive-behavioral therapy to reduce PTSD symptoms.
Given these findings, along with the body of research on the effects of red light on neurodegenerative disorders, it is possible that red light therapy could be used to slow or even reverse age-related cognitive decline – including dementia.
Improved Cognitive Function
Boosting brain power is possible not only in patients with degenerative brain disorders or brain trauma but also in healthy individuals with normal brain function. Faster learning, better memory retention and recall, and sharp thinking are just a few of the improvements in mental faculties that could be achieved through red light therapy.
There is a direct connection between enhanced brain function and specific brainwaves, which are electrical impulses in the brain. Brainwaves occur at various frequencies, from slow (delta, theta, and alpha) to fast (beta and gamma).
Research has shown that great achievers in any field spend more time in alpha, theta, and delta brain activity during waking hours, while most people spend most of their waking hours in a beta state of brain activity.
Beta brainwaves are associated with normal awake/alert brain function that’s necessary for focused attention. However, beta is also associated with stress, overthinking, and often, a disconnect from intuition and creativity. It’s a logic-driven state of mind that is focused on physical evidence, and often puts up a cognitive barrier against creative thinking.
Alpha brainwaves are associated with relaxed attention, such as when you’re absorbed in a complex task or enjoyable hobby. In alpha, creativity is less constrained by the “inner critic” so you are free to think creatively.
Theta brainwaves are associated with super learning, daydreaming, intuition, and creativity. Most people find themselves in an alpha state when they’re driving down a familiar stretch of road, lost in a daydream, and suddenly realize they’ve driven for miles without really paying attention to the act of driving. Theta activity is important for innovative thinking that is free of the constraints of logic or linear thought.
Gamma brainwaves are associated with “high mind thinking,” or rapid and efficient communication between different parts of the brain along with superior synthesis and processing of data.
During a 2012 study, researchers from Taiwan found that NIR light therapy at 830 nm increases alpha, theta, and delta brainwave activity, and decreases beta brainwave activity.
This is similar to the effects of deep meditation, which can have significant positive effects on cognitive functioning and is even known to slow or reverse aging-related neurodegenerative disorders.
A fascinating 2013 study by University of Texas researchers found that red light therapy also promotes increased activity in the brain’s prefrontal cortex, which is responsible for executive functions. These include focused attention, impulse control, setting and achieving goals, predicting, planning and anticipating, and coordinating sequences of actions.
The same study demonstrated other benefits to stimulating the brain with red and NIR light: The treatment has been shown to regulate neuronal function in cell cultures, animal studies, and clinical trials leading to improvements in attention, memory retrieval, mood, and reaction time.
The researchers suggest that transcranial stimulation with red light therapy could increase cognitive and emotional self-regulation functions.
Treatment of Degenerative Brain Disorders
With today’s aging population, age-related cognitive decline is becoming a more serious and widespread problem. Many people are interested in natural, non-invasive, and non-pharmaceutical therapies with no side effects, which makes red light therapy the ideal choice.
Thus, red light therapy is growing in popularity as a potential therapeutic treatment to slow or even reverse age-related cognitive decline and age-related brain disorders.
Research has shown that a decrease in activity and quality of mitochondria in the brain is associated with normal aging. Brain studies suggest that mitochondrial function can be improved using NIR light. This could be a game-changer for an aging population, especially those with a predisposition toward degenerative brain disorders.
Alzheimer’s is a severe form of dementia for which NIR light therapy shows great promise. In Hamblin’s 2019 study, patients with Alzheimer’s received NIR treatments and showed improvements in cognitive scores, better sleep, decreased anxiety, fewer emotional outbursts, and less wandering immediately after treatment.
Four weeks after treatment, some decline was noted in the original treatment results; but these declines may be mitigated with follow-up (maintenance) treatments.
Although more studies are needed, a 2020 animal study suggests that red light therapy might be an effective treatment for Parkinson’s disease in humans.
Since Parkinson's and Alzheimer's are both neurodegenerative disorders, the numerous encouraging findings from clinical trials on Alzheimer's could potentially hold promise for Parkinson's patients.
Treating the Brain at Home with Red Light Therapy
While many studies on traumatic brain injury and brain disorders use low-level (“cold”) lasers to deliver light to the skin, light-emitting diode (LED) light therapy devices are now being used more frequently thanks to advances in LED technology.
Today, LED red light therapy is delivered via low-risk devices, most commonly panels, which have significantly greater light energy output than handheld devices.
With the guidance of a medical professional, a high-light-energy output device, and consistent treatment, it’s possible that clinical results could be replicated at home.
Please note that red light therapy should not be considered a cure for damage from a brain injury, neurological disorders, or psychiatric disorders. Always work with your doctor on a treatment plan, and use red light therapy in a supportive role in helping promote healing on a cellular level.
Use a High-Light-Energy Output LED Device for Optimal Red Light Absorption
It’s important to use a high-output LED device that delivers the optimal wavelengths necessary for delivering the most significant therapeutic effects.
The PlatinumLED Therapy Lights BIOMAX series delivers a comprehensive multi-wavelength combination of the most therapeutic wavelengths of red/NIR light together for the most optimal healing spectrum available.
The NIR wavelengths delivered by the BIOMAX devices include 810 nm, 830 nm, and 850 nm to ensure maximum absorption into the brain tissue. As well, you will benefit from 630 nm and 660 nm red light, which has been shown to have skin-rejuvenating properties.
How to Administer Red Light to the Brain
Light absorption through the forehead is most common since hair can block some of the incoming light. Wear light-blocking goggles as you face the device because prolonged exposure to near-infrared light could potentially be damaging to your eyes.
You can also apply red light to the sides of your head, pulling the hair out of the way to allow access to as much skin as possible. This way, you can access other brain regions.
A 10- to 20-minute session several times a week could stimulate neurons and reduce inflammation on an ongoing basis, and could gradually lead to significant improvements in neuronal functioning.
Since red light therapy is considered safe for long-term use, you can continue bathing your brain in red light on an ongoing basis to keep your mind sharp and agile.
Red Light Therapy for Brain Health Can Provide Full-Body Benefits
From enhancing mental sharpness and boosting memory to improving thinking skills, red light therapy can benefit the brain in innumerable ways. It has also proved to be beneficial for treating brain injuries, degenerative brain disorders, and certain mental illnesses.
With so many research-backed neurological benefits, consider giving red light therapy a try. Although it should not be considered a cure, red light therapy’s cellular-level benefits can have a powerful ripple effect on your body's self-healing mechanisms.
Red light therapy is a scientifically backed and widely accepted treatment for anti-aging, as well as relief from neuropathy, arthritis joint pain, sacroiliac joint pain, low back pain, muscle aches, chronic skin disorders, hair loss, eye health, and enhanced physical fitness, just to name a few. Discover more about red light therapy on our Learn page. It could become your go-to for overall health and well-being.
And if you’re ready to get started today, check out the PlatinumLED Therapy Lights BIOMAX series, which delivers three NIR wavelengths that are scientifically proven to boost brain health.