Introduction

Imagine yourself sustaining a minor injury, only to encounter scepticism when sharing your pain. Now imagine navigating this scenario daily, with intensified pain and pervasive doubt, including from healthcare providers.^1,2 If you or a loved one is living with fibromyalgia, this may not be a hypothetical situation.

A disorder of pain processing, fibromyalgia is characterised by chronic muscle and joint pain, mood, cognitive issues, and intense fatigue - which, together, can have a severe impact on the quality of life of affected individuals.^3,4

With its exact causes still being uncertain, and symptoms varying dramatically between individuals, there is currently no standard treatment for fibromyalgia. Instead, current treatments (such as drugs, exercise and talking therapies) are symptom-focused, often leading to inadequate outcomes.⁵ Recently, however, a safe, non-invasive, and side-effect-free potential treatment option has emerged: light therapy.

Light therapy typically involves exposing the skin to low-energy wavelengths of red and near-infrared light to elicit a range of beneficial reactions inside the body. These reactions may address the disordered processes underlying a range of health concerns.⁶ As such, it's currently being investigated for use in at least 100 conditions, including fibromyalgia - and it has shown promising and long-lasting results.^7,8,9 Read on to discover how light therapy may be a potential source of relief for the complex and often misunderstood pain of fibromyalgia.

Understanding fibromyalgia

Although the exact origins of fibromyalgia are not completely understood, it’s thought to arise from an imbalance in the levels of certain chemicals in the brain. This imbalance changes the way the central nervous system (brain, spinal cord and nerves) transmits and receives pain messages.⁴ This imbalance leads to heightened sensitivity to non-painful stimuli (allodynia) and increased pain perception (hyperalgesia), and is also thought to be responsible for cognitive symptoms, fatigue and sleep-related issues.⁴

The onset of fibromyalgia has been linked to intense physically or emotionally stressful situations, and various existing conditions, although it can also develop gradually over time without any obvious triggers. Symptoms vary widely from person to person. This is likely due to the way each person’s central nervous system processes pain differently, as a result of a unique combination of genetic and environmental factors. These may include:

• Heightened pain sensitivity
• Chronic pain may be felt as an ache, burning, or throbbing throughout the body or at multiple sites (commonly including the head, chest, arms, legs, abdomen, back and buttocks)
• Cognitive challenges e.g. difficulties in concentration and memory (often referred to as "fibro-fog")
• Muscle stiffness
• Headaches
• Irritable bowel syndrome (IBS)
• Sleep difficulties, often leading to fatigue
• Depression and/or anxiety

While this lack of specificity surrounding its causes and symptoms complicates both diagnosis and treatment, it points towards the need for both individualised and multidisciplinary approaches. 

A promising option for the said approach is light therapy, which can be used alongside prescribed treatments for fibromyalgia and tailored to specific needs. 

What is light therapy?

Light therapy goes by around 60 different names, frequently used interchangeably. The most common of these are red light therapy, low-level laser/ light therapy (LLLT), phototherapy and photobiomodulation (PBM) - although it’s worth noting that photobiomodulation is in fact the scientific term for the process by which light therapy is thought to work.⁷

In particular, red light therapy (which uses red and/or near-infrared light) is rapidly gaining traction for its wide range of health benefits. These two types of light differ in the size of their wavelengths. Red light uses shorter wavelengths so it works closer to the skin’s surface, while near-infrared light uses longer wavelengths, penetrating the skin more deeply - but each has its own set of advantages.¹⁰

Although shorter wavelength green light and broad spectrum bright white light have also begun to garner interest for potentially beneficial effects, they currently have fewer applications and less research to support their benefits. As such, red/ near-infrared light therapy will be the main focus of this article.^10,11,12 

Many different wavelengths of light have been applied across a variety of uses so far. The optimal wavelength range depends on the condition being treated. Treatment regimes vary but usually involve shining the light source onto the skin at the site of concern, or whole body, for short periods of time over several sessions. For example, you may have 10 to 20-minute sessions three times a week spanning several weeks or months.¹³

Importantly, unlike cancer-causing UV rays from the sun and tanning beds, the low-energy wavelengths from these light therapies are safe and cause no serious side effects.¹³

How does light therapy work?

Light therapy is thought to work via the process called photobiomodulation (PBM), and is thus often referred to as such. This describes the result of interactions between photons (particles) of light on our cells’ powerhouse; the mitochondria. 

Mitochondria are responsible for generating our body’s energy in the form of adenosine triphosphate (‘add-enno-seen try-fos-fate’, ATP). Photons of these specific wavelengths penetrate the skin and reach the mitochondria, increasing their energy and, as a result, the production of ATP.⁶

While the precise mechanisms of photobiomodulation remain unclear, this increased energy production in our cells is thought to alleviate many disease-related processes including inflammation and oxidative stress while promoting tissue repair, thus contributing to overall cell health.^6,14,15

How can light therapy help in the management of fibromyalgia?

Restoring essential brain chemicals to reduce pain, improve mood, and protect nerves

In fibromyalgia, the levels of a chemical messenger (neurotransmitter), called serotonin are reduced. Serotonin plays an important role in dampening down pain signals by blocking a pain-signalling neurotransmitter called substance P.^4,16 A lack of serotonin in the central nervous system has also been associated with many mental health conditions, including depression and anxiety.¹⁷

Near-infrared light may be able to restore serotonin levels in the brain. A study experimenting on mice reported on the antidepressant and anti-anxiety effects of near-infrared laser light, which coincided with an increase in serotonin levels and decreased levels of nitric oxide.¹⁸ Nitric oxide is a chemical that increases pain sensitivity in excess (a state known as nitrosative stress), as found in people with fibromyalgia, partly due to mitochondrial dysfunction.^19,20

Nitrosative stress is also involved in cell death, particularly of nerve cells, which red light has been shown to potentially protect and regenerate nerve cells. This suggests that the pain-alleviating effects of light therapy may be partly due to the restoration of normal nerve signalling.^21,22

A review of studies examining light therapy for clinical depression concluded that, although larger scientific trials are needed to determine the true effectiveness of red and near-infrared light therapy for this condition, it appears to be a promising new option. This highlights its potential ability to reduce inflammation and oxidative stress while promoting the generation of new neurons in the brain.²³

Reducing inflammation to lessen pain sensitivity and fatigue

Another contributory factor towards increased pain in fibromyalgia is inflammation in the brain (neuroinflammation). This involves the activation of the brain’s specialised immune cells, called microglial cells, which release small proteins known as cytokines. 

In people with fibromyalgia, levels of pro-inflammatory cytokines (which promote inflammation), are greater than anti-inflammatory cytokines, (which reduce inflammation). Not only does this neuroinflammation increase pain sensitivity, but has also been linked to other major symptoms of fibromyalgia, including depression and fatigue.^10,24

Red-light exposure has been shown to reduce levels of these pro-inflammatory cytokines, thereby decreasing brain inflammation and contributing to heightened pain sensitivity.¹⁰ Near-infrared wavelengths can also support the re-balancing of cytokine levels while reducing inflammation.²⁵ This inflammation-attenuating effect may also serve partly as an explanation for improved mood and energy from light therapy.^9,26,27,28 

Improving sleep quality

Lower levels of serotonin in people with fibromyalgia may be linked to the reduced production of melatonin - a hormone that plays an important role in regulating your sleep-wake cycle. This may partly explain the symptoms of sleep disturbance.²⁹ Red light may be able to regulate levels of melatonin, leading to improved sleep quality, although this has only been demonstrated in a small group of healthy individuals so far.³⁰ Red and near-infrared light have also been shown to improve brain function during sleep by supporting the natural clearance of toxic waste products.³¹ 

Given the undeniably crucial role of sleep in your body’s ability to repair damage and fend off serious chronic health conditions, improving sleep quality in these ways may provide a better night’s rest, reducing daytime fatigue and augmenting other treatment benefits.

What do scientific studies so far tell us? 

Evidence for these benefits can be observed through scientific studies examining various forms of light therapy in people with fibromyalgia.

One clinical study investigated the effects of both exercise (a recommended treatment for fibromyalgia), and red-light as well as infrared LED light on pain management and quality of life in 160 women with fibromyalgia.⁸ Significant reductions in pain were found as a result of light therapy and exercise, with the greatest effects being observed for women allocated to follow the exercise plan combined with light therapy. 

Findings supporting the synergy between light therapy and exercise have been corroborated by critical review of 9 trials testing low-level light therapy in 325 participants with the condition.²⁶ This doesn’t come as a surprise however, as light therapy has been shown to improve exercise performance in people with fibromyalgia. 

Taken together, this evidence suggests a role for light-therapy in facilitating the widely recommended multidisciplinary approach by removing the barrier of pain-induced physical limitation that prevents many with the condition from participating in physical activity.^32,33

More recently, researchers investigated the use of combined red and near-infrared LED light therapy on the whole body over the course of 6 weeks, using 21 participants with fibromyalgia.⁹ Promisingly, they found improvement in the overall quality of life and positive changes across a range of symptoms that lasted even 24 weeks after treatment. These symptoms included:

• Pain, stiffness and tenderness
• Fatigue and sleep disturbances 
• Depression and anxiety
• Cognitive performance 

Such results reflect previous reports from three research reviews, all of which reported improvements in a similar set of symptoms across analysed studies from red and/or near-infrared light, without any negative side effects.^26,27,28

Together, these findings form a strong foundation for further, larger-scale and more consistently designed trials examining red/near-infrared laser and LED light therapy, ideally with the identification of an optimal light therapy protocol, in the treatment of fibromyalgia.

Summary

By harnessing the power of specific wavelengths of red and near-infrared light, light therapy appears to aid in the restoration of various chemical imbalances at the root of fibromyalgia. As such, it stands as a promising avenue for managing the condition, offering a safe, non-invasive and drug-free approach to alleviate widespread pain as well as cognitive and mental health-related symptoms. The effects that may be amplified alongside the recommended treatment of exercise in particular. 

While ongoing research continues to explore the full scope of its benefits, current findings suggest that light-therapy could be a valuable addition to the toolkit for enhancing overall well-being. As we look ahead, the potential for light therapy to contribute to a more comprehensive and multifaceted approach to fibromyalgia care is indeed an exciting prospect.