Red Light Therapy and Mental Health

Red light therapy (RLT), also known as photobiomodulation or low-level laser therapy, has emerged in recent years as a promising treatment for a wide range of health conditions.

Research indicates that RLT can improve mitochondrial function, reduce inflammation, and stimulate healing processes in the body.

An expanding area of research is examining the effects of RLT on mental health conditions such as depression and anxiety. This article explores the current evidence regarding RLT and mental health.

What is Red Light Therapy?

Red light therapy involves exposing the body to low-level red and near-infrared light for therapeutic benefits.

• These wavelengths of light can penetrate deeply into tissues where they interact with chromophores – light-sensitive structures like mitochondria and hemoglobin.
• This initiates signaling cascades that ultimately lead to beneficial cellular and tissue changes.

Most RLT devices emit light in the 600-950 nm wavelength range. This can be delivered via lasers or light-emitting diodes (LEDs). LEDs are generally preferred as they cover a wider spectrum of wavelengths.

The optimal dose depends on factors like the condition being treated and the area of irradiation. Typical RLT protocols involve exposures of a few minutes per session, with multiple sessions per week.

RLT for Depression and Mood Disorders

An increasing number of studies are examining whether RLT may have antidepressant and mood-boosting effects.

There are several ways in which RLT could potentially improve depressive symptoms:

Boosting Brain Cell Function

• Animal research indicates RLT promotes neurogenesis – the growth of new brain cells in areas like the hippocampus. This may directly counteract the effects of stress and depression on the brain.
• By improving mitochondrial function and cellular energy production, RLT helps brain cells stay healthy and active. Impaired mitochondrial function is linked to mood disorders.
• RLT reduces harmful inflammation in the brain which is increasingly tied to depression.

Increasing Serotonin

• Low serotonin levels contribute to depression. Preliminary evidence in animals indicates that RLT can increase serotonin production and availability in the brain.

Modulating Other Neurotransmitters

• Research shows RLT can influence levels of dopamine, noradrenaline, GABA, and glutamate – key neurotransmitters involved in regulating cognition, mood, and motivation.

Enhancing Endogenous Opioids

• Endogenous opioid peptides help produce feelings of pleasure and well-being. An animal study found red light exposure increased beta-endorphin levels in the blood.

Clinical Research on RLT and Depression

While still an emerging area of study, initial clinical trials are supporting the antidepressant effects of RLT:

• A randomized placebo-controlled trial in adults with major depressive disorder utilized daily RLT sessions to the forehead area for four weeks.
• The RLT group had significant remission rates of depression versus the placebo group (71% vs 22%).
• A pilot study exposed individuals with symptoms of anxiety and depression to a specialized near-infrared lamp emitting wavelengths between 600-1150nm.
• After ten sessions over two weeks, over 70% of participants had at least a 50% reduction in standardized depression scores.

Several other small clinical studies using varied RLT protocols have also noted reductions in depressive symptoms from RLT versus sham treatments.

Larger-scale randomized controlled trials are still required to confirm and expand on these early findings.

Table 1: Key Findings from Clinical Trials on RLT for Depression

RLT for Anxiety

Growing research also indicates therapeutic potential for using RLT to reduce anxiety symptoms by:

• Increasing calming GABA activity in the brain
• Lowering excessive glutamate activity is often seen in anxiety
• Reducing inflammation in brain regions linked to fear and anxiety
• Boosting alpha brain waves associated with wakeful relaxation

An open-label trial provided an 810 nm RLT device to adults with generalized anxiety disorder to self-administer twice a day for 4 weeks.

Anxiety scores were reduced with the RLT treatments, and the effects persisted at a 3-month follow-up.

Determining Optimal RLT Protocols

While the initial research is extremely promising for RLT benefiting mood and anxiety issues, optimal treatment parameters still need to be refined. Areas requiring further investigation include:

Wavelengths – Should specific wavelengths or wavelength ranges tailored to mental health be used?

Body Areas Targeted – Which regions should be irradiated – e.g. the forehead or whole-head exposure?

Light Sources – Are LED clusters or more concentrated lasers more effective?

Session Duration & Frequency – What durations and number of sessions a week provide the greatest mood improvements?

Adjunct Treatments – Can RLT be combined with other interventions like psychotherapy or supplements to enhance effects?

As the most efficacious RLT approaches are elucidated with further research, they may one day play a prominent role alongside established treatments for mood and anxiety issues.

Is RLT Safe?

RLT, when administered correctly from reputable devices, seems to be very safe with a low risk of adverse effects.

• The light energy delivered is not sufficient to damage the skin or eyes. Mild side effects occasionally reported include headaches or fatigue after treatment.
• RLT should be avoided in those with light-sensitive conditions or on photosensitizing medications.

Additional Applications Related to Mental Health

Aside from directly treating mood and anxiety disorders, RLT could also benefit mental health in other interrelated ways:

Providing Non-Pharmacological Pain Relief

Chronic pain and mental health issues often co-occur and can exacerbate one another. By reducing inflammation and increasing natural opioids, RLT can safely alleviate various chronic pain conditions to improve mental health indirectly.

Enhancing Sleep Quality

Sleep disruption goes hand-in-hand with anxiety and depression. Research indicates that RLT can help normalize circadian rhythms and melatonin secretion to promote higher-quality sleep.

Accelerating Healing from Traumatic Brain Injuries

RLT has shown preclinical efficacy in improving functional recovery and reducing lesions caused by traumatic brain injury (TBI) which often leads to neuropsychiatric symptoms.

Improving Stress Resilience

As a potent anti-inflammatory therapy, RLT may mitigate the toll psychological stress takes on the mind and body over time. This could strengthen stress resilience and help prevent stress-related mood disorders.

Table 2: 6 Potential Benefits of RLT Related to Mental Health

Conclusion

In summary, red light therapy is an emerging therapeutic tool under active investigation for wide-ranging benefits to both physical and mental health.

• Initial research indicates potential for using RLT to improve mood disorders, reduce anxiety, and support mental wellness through various biological mechanisms in the brain and body.
• More rigorous clinical trials are underway to help establish optimal treatment protocols.
• RLT is affordable, non-invasive, well-tolerated, and accessible for self-administered at-home use – making it an appealing intervention should efficacy be definitively established by future studies.

While not a replacement for proven psychotherapeutic or pharmacological approaches, RLT could become a viable adjunct or stand-alone treatment option for some individuals struggling with depression, anxiety, and other mood imbalances.

References

1. Van den Berg, J., Caan, M., Marquering, H., & Reneman, L. (2024). The Association Between Amygdala FMRI Response During Emotional Processing and Mood Disorder Symptom Severity and Recurrence in the UK Biobank Cohort. Available at OSF.
2. Effects of Near-Infrared Light on Well-Being and Health in Human Subjects with Mild Sleep-Related Complaints: A Double-Blind, Randomized, Placebo-Controlled Study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9855677/