afit 20% of adults in the United StatesMore than 50 million people suffer from chronic pain. Although the causes are numerous, including arthritis, cancer, musculoskeletal skeletal disorders, migraines, fibromyalgia, and more, solutions are limited.
Over-the-counter painkillers often do nothing. physical therapy, messageAnd the Acupuncture It helps sometimes – but not always. Prescription opioids may provide short-term relief, but at a price. at least Three million Americans Currently addicted to drugs.
Researchers are now exploring another potential alternative that is safe, affordable, comes with few or no side effects and no risk of addiction: exposure to green light. Although recent science and research is by no means conclusive, studies in recent years have found that exposing people to light across a green wavelength – either by having them sit in a dark room lit by green LED light strips or by giving them to wear glasses with Green – can reduce pain intensity and frequency of migraine attacks, fibromyalgia, and chronic musculoskeletal pain. It can also relieve anxiety and fear associated with chronic pain.
In a study presented October 23 in annual meeting Of the American Society of Anesthesiologists in New Orleans, Dr. Padma Gullur, vice chair of anesthesiology at Duke University, reports on an experiment she conducted in which 34 fibromyalgia patients were tasked with wearing differently colored tinted glasses, four hours at a time. day for two weeks. Ten of the patients wore blue-lensed glasses, 12 wore clear glasses, and 12 wore green glasses. At the end of the study period, people who wore green glasses were four times more likely than those in either group to report a reduction in their anxiety about their pain, as well as a decrease in their dependence on opioids.
Golor used commercially available glasses for the study and tested each with a spectrophotometer to ascertain exactly the wavelength of green light each pair produced. I also tested a pair of glasses for each person at the end of the study to confirm which one got the wavelength. “What surprised us most was that at the end of the study, patients were so happy with the results, they didn’t want to put their green glasses back,” she says.
Although the Gullor study is small, it is not the only one of its kind. At the University of Arizona Dr. Mohab Ibrahim is Professor of Anesthesia, Neurosurgery and Pharmacology. Together with Laurent Martin, Assistant Professor of Anesthesia. And their other colleagues have published six papers in the past four years that demonstrate the power of green light to relieve pain. in one, Published in 2020 in the magazine a headache (which means “headache”), investigators recruited 29 migraine sufferers and exposed them to one to two hours of green LED lights — which the university provided people to install in their homes — every day for 10 weeks in a darkened room. The treatment reduced headache days by 70% in people with episodic migraines compared with their primary headache frequency, and by nearly 60% in those with chronic recurrent migraines. (The group exposed to white LEDs saw no change.) In another paper, published the following year in the magazine pain medicineIbrahim recruited 21 fibromyalgia patients, performed a similar treatment and found that people who reported their pain while eight out of 10 when exposed to white light had their rating dropped to less than five when exposed to green.
“There are neural pathways that start in the eye and can be traced back to several brain regions,” says Ibrahim, who also serves as medical director of the Comprehensive Pain and Addiction Center at Banner University Medical Center. “Some of these areas are significantly involved in pain modulation.” Through a mechanism that is not yet fully understood, the green light appears to cut this connection, providing relief without medication, or at least not as much.
“This is a simple approach,” Ibrahim says. “There is still some skepticism, and rightly so. When you make an extraordinary claim, you have to have extraordinary evidence. But the more studies and research that gets funded, the closer we get to a critical mass of evidence that says, well, there is Something is really going on here.”
break the cycle
For Jennifer Denardo, 64, a retired Tucson former hospitality worker, the problem started when she was 18 and went skateboarding after, as she describes it, drinking more wine than she put in the spaghetti sauce she was making that evening. She had a spill and landed face-first on the pavement, breaking her nose and breaking a bone in her neck. The pain was sharp, and while she was being treated, the doctor responded immediately with tablets.
He said: Here, take this. This will make you feel better.
They did – for a while. But that bad night led to complications including fibromyalgia and migraines headacheShe eventually required surgery to fuse two discs in her neck. Her pain turned chronic, and she took strong painkillers for years.
“I’ve tried everything,” Denardo says. Massage therapy, stretching exercises, Tai Chi. And many times, I ended up with the prescription in my hand.”
Finally, in 2020, I attended the Comprehensive Pain and Addiction Center while Ibrahim was beginning one of his experiences with green light therapy. “He said, ‘Are you going to take care of this study,'” she remembers. “I said: I will do anything.”
For the next 70 days, Dinardo would spend two hours each day in a room in her house lit only by green LEDs, reading and listening to music to pass the time. After 30 days, her chronic pain began to fade. Soon, she stopped using all painkillers, and has been free of any medications since she started treatment two years ago. She kept the LEDs on, and while she doesn’t use them every day anymore, she turns them on whenever she has neck pain, headache, or fibromyalgia.
“You can feel the difference,” she says. “It’s really amazing.”
How does green light relieve pain?
Scientists don’t yet know why green light appears to help treat painful conditions like fibromyalgia and headaches, but they have some ideas. Gullor thinks the answer may lie in green light’s ability to stimulate melanopsin, a light-sensitive neurotransmitter found in the eye responsible for regulating pupil dilation and constriction. Melanopsin also interacts with periductal gray matter, a structure in the upper brainstem that plays a role in pain processing. She speculates that melanopsin may activate an inhibitory pathway that does not treat pain, but rather shuts it down. I found that not just any old green light would do the trick, but specific frequencies for it.
A product Ibrahim develops with Luxxon Therapeutics that builds LED lights directly into eyeglass frames
“You might think that the green peak wavelength — absolute green — would be more effective,” she says. “But what we’ve found for chronic pain is that lower wavelengths and higher wavelengths — more toward the ends of the green spectrum — seem to help patients.” This limits people’s options to try this treatment for themselves, as simply purchasing any green cups available in the store does not guarantee the appropriate wavelength, which can only be tested with a spectrophotometer.
For now, this is just a theory. But Gullor is currently developing a new study in which the brains of pain patients who wear green glasses are examined using functional magnetic resonance imaging (fMRI) to see if the inhibitory pathway is actually present.
Ibrahim and colleagues are looking at other brain regions that play a role in pain processing, particularly the rostral ventral medulla (RVM), also located in the brainstem. A specific type of brain cell, known as GABAergic neurons, produces a protein known as c-Fos, which in turn activates the RVM, completing the neural circuit that leads to pain. In animal studies, mice exposed to green light produced less c-Fos, which reduced the activity of GABAergic neurons and disrupted the pain pathway.
“We assessed the amount of GABAergic cells expressing c-Fos, and found that green light lowers their production,” Ibrahim says. “In general, light reduces the activity of cells, which, if stimulated, would enhance pain.”
Read more: 5 ways to deal with migraines at work
In other studies, Ibrahim looked at the front end of the inhibitory pathway — the cells in the eye that react to green light and cycle through the analgesia. in One study in 2022published in Clinical Medical Insights: Case ReportsGreen light has been found to have analgesic effects even in a color-blind patient who also suffers from chronic headaches. This study may seem to indicate that there is no more than placebo effect At work, where a person expects to feel pain relief and so does he. But Ibrahim says otherwise. The two primary types of cells in the eye that process light and color are known as cones and rods, for their distinctive shapes, and cones are the ones that malfunction in color blindness. But there is a third type as well, known as photosensitive retinal ganglion cells, and these cells are not affected in people with color blindness. Ibrahim believes that these cells may be responsible for the pain relief.
“It is one of our hypotheses,” he says, “that the effect of green light passes at least in part through these light-sensitive cells.” Golor advances this idea, noting that these same cells also contain melanopsin, which in her models plays a central role in pain relief.
More research in humans is needed. Nor do its proponents believe that green light therapy will completely replace other forms of pain treatment — including pharmaceutical drugs. Will it replace traditional medicine? Ibrahim says. “I don’t think so. That is not the intent. The intent is to reduce dependence on medications immediately because these are all tools realistically.”
However, green light therapy is already going commercial. Many manufacturers sell and market green LED lighting systems online for pain relief, although there is no guarantee that the wavelength of green used in the products will be effective.
In an effort to create something, Ibrahim and Luxxon Therapeutics are combining glasses with the LED method: building green LEDs directly into the frame of a pair of glasses so that they shine in the user’s eyes during treatment sessions.
Ibrahim says exposure to the green light checks a lot of treatment funds. “The first is safety, then efficacy, then price, then commitment,” he says. It may be that the latter—adherence, or patients’ commitment to adhere to treatment—is most indicative. “Chronic pain patients will do just about anything to get rid of the pain,” Ibrahim says.
Dinardo agrees. “Just sitting in that room with the green light on, is such a change for me — and that’s a blessing,” she says.
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