For thousands of years, people have used sunlight as a means to aid health and even cure illness. But the concept has gone in and out of favor over the course of time.
Some of the logic related to sunlight began in China around 6,000 BC. At that time, Chinese architects began building homes to face south so that the sun would heat the interior, a practice that continues even today. While windows were likely no more than a gap in the wall at the time, you can still imagine families gathering around to soak up the light and heat. Finally, the trend of solar-heated homes began to catch on in Greece and even Rome. Learn more about solariums.
Then, in the 1900s, research by Augusta Rollier led to the establishment of solaria — buildings designed to optimize exposure to sunlight — throughout Switzerland for the express purpose of sunbathing, which provided impressive results for fighting tuberculosis, smallpox, lupus, and even chronic diseases like arthritis.
But by the middle of the 20th century, the American Cancer Society began demonizing sun exposure as a significant cause of skin cancer.
However, doctors, scientists, and clinical research is demonstrating that consistent exposure to sunlight is actually a critical component of overall health.
Almost all life on earth needs sunlight for many essential functions. It’s hard to ignore its importance for our emotional and physical health as well. We did not evolve in the darkness. The fact that our bodies use UV wavelengths to produce vitamin D has been well established. Read more about vitamin D here.
Is Sunlight Dangerous?
Several recent studies have come to the conclusion that consistent sunlight exposure actually reduces the chances of getting melanoma, and instead increases the survival rate. Also, throughout the ages, regardless of their geographical location, large groups of people have been exposed to nearly continuous sunlight. We evolved having sunlight.
So why did the melanoma epidemic not hit until the 1970s? And if sunscreen is the solution, why have melanoma rates increased over 200% since 1973 — even while the U.S. sunscreen industry has expanded from $18 million in 1972 to around $2 billion today?It’s hard to believe that sunlight was the major problem, nor sunscreen the solution.
A recent review of many such studies published in the European Journal of Cancer Prevention concluded that “there is accumulating evidence for sunlight as a protective factor for several types of cancer.” Sadly, many people still live under the incorrect premise that sunlight is damaging and harmful.
The reality is that we have become so disconnected from natural sunlight that our bodies aren’t equipped to handle its under-appreciated benefits. You may be surprised to learn that as your body gets sunlight in the morning, you can actually prepare your cells for the effects of UV light later in the day. And amazingly, the wavelengths in evening sunlight have a natural repairing effect. That’s because red and infrared wavelengths, which are delivered in higher concentrations in the morning and evening, have the unique ability to boost mitochondrial function. This, in turn, enables our cells to both withstand the stresses — and harness the benefits — of UV light. In addition, exposure to sunlight as the seasons change allows our skin to develop a tan, which also forms a natural protection against the stronger UV wavelengths during the summer months.
So the evidence suggests that sunlight might not be the bad guy, after all, we just need to develop a better understanding of how sunlight affects our bodies, and how to harness its potential to improve our health.
The Benefits of Receiving Sunlight
Our retinas are connected directly to the suprachiasmatic nuclei of the hypothalamus gland, which acts as the master circadian pacemaker of the body. Because of this, light received through your eyes plays a critical role in hormonal functions including melatonin production, which regulates our sleep. Quite literally, your body knows to shut off this hormone through exposure to morning sunlight. This type of exposure early in the day also helps produce melatonin later in the evening, when light is absent. Even more amazing, the hypothalamus gland, which is controlled by light, is responsible for controlling body temperature, thirst, hunger, and emotional activity — in addition to regulating your hormones and circadian rhythm!
Dopamine is another chemical that is regulated by light and released in the brain. It functions as a neurotransmitter and is closely tied to the emotions of reward and pleasure. In fact, many addictive drugs increase dopamine neuronal activity. Not surprisingly, studies have demonstrated that light exposure is tied to increased dopamine production. So it’s clear that light received through our eyes plays a much more powerful role than most of us realize.
How You Can Benefit from More Light
Getting as much natural sunlight as possible is clearly important. For example, receiving morning sunlight correctly sets your circadian rhythm. However, nowadays, most of us find it challenging to spend hours in the sun — at the right time of day — on a regular basis. Our busy schedules just don’t allow for more time in the sun. In fact, it’s estimated that Americans spend more than 90% of their time indoors.
Because this is the case for most of us, a great way to receive the healthy wavelengths of light is by using a light therapy device. One way to think of red light therapy is as a supplement for your health. Dietary supplements help fill out the vitamins your body needs, and regular red light therapy sessions help fill in the lack of natural light our bodies need.
There are many proven benefits of receiving certain wavelengths of natural sunlight directly through our skin and bodily tissues. One aspect that has received little attention is related to the cellular processes affected by certain wavelengths of light.
Researchers in the field of light therapy, or photobiomodulation (PBM), have discovered some incredibly powerful functions derived from wavelengths of light in the optimal window. Improved mitochondrial function, which impacts virtually all cellular metabolic activity, has been widely demonstrated to improve health in a number of ways — including enhanced muscle recovery, reduced inflammation, increased testosterone, and better overall skin health.
In addition to these clinically-proven benefits, several studies have demonstrated that certain wavelengths of light can increase blood flow and assist in the formation of new capillaries. Dr. Gerald Pollack explores this concept in more detail in his award-winning book, The Fourth Phase of Water.
In conclusion, scientists are really just beginning to understand the crucial role that light plays in our overall health. But recent evidence strongly suggests that exposing our bodies to the right kind of light can lead to some wonderful benefits.
Klepeis NE, Nelson WC, Ott WR, et al. The National Human Activity Pattern Survey (NHAPS): a resource for assessing exposure to environmental pollutants. J Expo Anal Environ Epidemiol. 2001 May-Jun;11(3):231–52.
Which is the vitamin that is not normally found in any vegetarian food? Vitamin D.
Scientists have defined vitamins as organic (carbon-containing) chemicals that must be obtained from dietary sources because they are not produced by our bodies. Vitamins play a crucial role in our body’s metabolism, but only tiny amounts are needed to fill that role.
The discovery of Vitamin D was the culmination of a long search for a way to cure rickets in the 1920s, a painful childhood bone disease. Within a decade, the fortification of foods with vitamin D was on the way, and rickets became rare in the United States. However, research results suggest that vitamin D may have a role in other aspects of human health.
Vitamin Dit’s absent from all-natural foods except for fish and egg yolks, and even when it’s obtained from foods, it must be transformed by the body before it can do any good. That’s why the energy of the Sun is so important.
The sun’s energy turns a chemical in your skin into vitamin D3, which is carried to your liver and then your kidneys to transform it into active vitamin D.
The main cause of vitamin D deficiency is a lack of direct sunlight
Humans, day by day, spend less time outdoors. Most people work indoors now, and many of our leisure pursuits occur in an indoor setting as well. What’s more, when we are outside, many people avoid the sun as much as possible. The result is the body not absorbing enough UVB rays to create the amount of vitamin D it requires. Often, symptoms of vitamin D deficiency are quite mild. When noticed, they mainly consist of:
Frequent bone fractures.
Muddled thought processes.
Soft or deformed bones.
Though you may not notice any symptoms, that doesn’t mean that vitamin D deficiency doesn’t present serious health risks. These include:
Children may develop severe asthma.
Immune system problems, raising your risk of infection.
Insulin resistance, impacting your body’s ability to process sugar and increasing your risk of diabetes, multiple sclerosis, and glucose intolerance.
Osteoporosis, a condition that includes brittle bones that are more likely to fracture.
Reduced cognitive function.
Rickets, a bone disease that causes soft bones and skeletal deformities.
Other conditions that would happen without enough sunlight
Less chance of having a baby
Without sunlight, there will be more melatonin in a woman’s body. This is a hormone that suppresses fertility, thereby reducing her chances of conceiving a baby. Moreover, women who get less sunlight reach their menopause earlier than those who are exposed to the Sun. Men can also suffer from a lack of sunlight; it directly influences testosterone levels.
It’s believed that if children don’t get enough sunlight, they’ll be more at risk of developing multiple sclerosis, a disease of the central nervous system when they become adults.
All those aches and pains
Without sunlight, be prepared to get more pains all over your body. Sunlight helps to warm the body’s muscles and reduce the pain caused by inflammatory conditions such as arthritis.
No sunny emotions
Without sunlight, we would be forever stuck with the seasonal affective disorder (SAD), commonly known as the winter blues. It’s a form of depression that is specifically caused by a lack of sunlight. Artificial light cannot fully replace natural sunlight.
Recent evidence suggests that vitamin D may help prevent many disorders, such as diabetes, multiple sclerosis, rheumatoid arthritis, chronic obstructive pulmonary disease, asthma, bronchitis, premenstrual syndrome, increased blood pressure, strokes and heart attacks, and even cancer. Low serum vitamin D levels are also associated with being overweight, abdominal obesity, metabolic syndrome, stroke, and diabetes. In addition, having lower blood vitamin D levels for a long period is associated with increased heart attacks and all-cause mortality.
In Kaiyan medical, we believe in the benefits of light. We believe in healing without chemicals. With our lights, we want you to have the best version of yourself. More at kaiyanmedical.com
A circadian rhythm is a natural bodily process that happens roughly every 24-hours. It’s a cycle, like sleeping & waking, or eating & digesting, that completes & restarts daily. Our circadian rhythms are tied to the earth’s rotation and light/dark cycle, but they are also encoded in our genes.
We are naturally diurnal animals, meaning we’re awake during the day and asleep when dark. It’s how we evolved, like how mice are designed to be nocturnal mammals that sleep during the day and forage at night.
Another example of an internal process operating on a circadian rhythm is the human digestive system. Our digestive system cannot create and burn fat simultaneously, so our cells alternate according to a circadian rhythm. When we’re awake and actively taking in calories, our digestive system breaks down food and creates stored fat. When we sleep, our stored fat keeps our bodies fueled.
Going against your natural rhythms and not establishing routines can have systemic effects, like sleep disturbances and metabolic slowdowns. Poor sleep can affect hormone production as well as your ability to recover from injury and overcome inflammation.
Dr. Satchin Panda of the Salt Institute is the author of the book The Circadian Code, which discusses circadian biology in much greater detail. Dr. Panda writes about three “core rhythms” that our body aligns with.
Circadian Rhythm & Sleep
Without artificial lighting and screens, we will typically sync with the planet’s day/night cycle: rising with the sun and sleeping when it’s dark. We’ve come a long way from those origins, but our bodies are still designed to work with an abundance of light during the day and restful sleep when it’s dark at night. If you sleep from 5 am to 2 pm every day, you may get enough sleep, but the quality of your sleep will likely not be as good.
Our bodies work best when we’re getting restful sleep every day. But even if you’re getting 7–8 hours, you may not be aligned with your body’s optimal sleep cycle.
Circadian Rhythm & Eating
According to Dr. Satchin Panda, our body has an 8 to 10-hour window for optimal food intake that begins when we take our first bite in the morning. Digestion of even a small bite of food takes hours, and efficiency slows dramatically once we’re outside that window. There’s a set window of time because our internal organs follow circadian rhythms to do their jobs, like processing food and liquids.
The stomach, liver, pancreas, and other key internal organs work best when our eating aligns with our circadian rhythm. Following a routine or schedule with your eating that allows your body to operate along the same patterns is more efficient for your digestion, nutrient absorption, and overall metabolism. Limiting your food intake to a specific window of time is also ideal.
Circadian Rhythm & Recovery
Our bodies are programmed to shift into a night mode after the sun goes down. Heart rate and breathing slow, body temperature lower, and we usually go to sleep. When you’re exercising after dark, your body has to work hard to make and use all that energy and then start the recovery process late in the day. This can clash with your sleep cycle and the circadian rhythm of digestion & eating, making your recovery and fat burning less efficient.
It might seem obvious, but our bodies are made to be active while we’re awake. Physical activity during the day, in line with our sleep and digestion cycles, is a key part of a balanced, healthy lifestyle. Exercise has too many health benefits to list, but it’s most beneficial when you get your main activity done during the day, not late at night.
Light & Circadian Rhythms
Light intake is one of the most important factors in sleep and circadian rhythm. The brain interprets light as a sign of when to be asleep and awake. Your circadian rhythm is designed around the sun, but the bright lights and screens of modern life can knock the body’s natural signals and rhythms out of whack. If you stare at a bright screen at midnight, your body may be tired, but your brain is getting the message that it’s time to be awake. Too much bright, artificial light after dark can make it much more difficult to sleep and establish a healthy wake/rise schedule.
Two hormones that regulate the sleep cycle are directly affected by light. Cortisol, a steroid hormone produced by your adrenal glands, helps wake us up and keep us going. Cortisol levels tend to be highest in the mornings and lowest when we’re in our deepest sleep, typically around 3–4 am. Bright artificial light can stimulate cortisol levels that keep you awake, as documented in clinical studies.
The hormone melatonin is a counterpart to cortisol. Produced by the pineal gland, melatonin helps you fall asleep and stay asleep. Your body usually starts producing melatonin in the early evening, when you’re starting to wind down and get closer to bedtime. Bright light, especially bright blue light from phones and computers, has disrupted melatonin production.
As humans, we are made of energy and fueled by light. While nutrition and exercise play a role in our well-being and health, light plays a crucial role in us functioning optimally. New and groundbreaking research is unearthing a new understanding of how our cells function and the evidence points to the power of light.
Through technological advancements in science, it’s discovered that our bodies operate similar to a battery. Wavelengths of light give us power, while our overall health determines our ability to receive and maintain the energy from light. And this is where light therapy comes into the equation.
What is Red Light Therapy
Science has proven that our bodies interact with specific wavelengths that benefit our bodies in various ways.
Red light therapy devices, such as light therapy masks, shine red and near-infrared light onto the skin, stimulating the production of adenosine triphosphate (ATP) within the mitochondria. By stimulating ATP, damaged cells heal, and new cells are produced faster than normal. But we’ll talk more about that in-depth a little later.
Red light therapy comprises both red light and infrared wavelengths, penetrating through the skin’s layers, right into the cells. Red light wavelengths boost collagen and elastin and improve cell communication. It penetrates superficially and helps aid various skin conditions.
Near-infrared wavelengths stimulate healing, increase mitochondrial function, and improve blood flow and tissue oxygenation. Near-infrared wavelengths penetrate deeply into the body.
Recharging Your Body From Within
At the core of your body’s healing capabilities are the mitochondria. The mitochondria play a vital role in your internal organs and tissue, including the liver, skin, heart, and muscles. It’s in charge of the body’s energy supply via ATP (adenosine triphosphate).
With both working together, they provide energy to our body and maintain the cell cycle and growth. This is why you’ll often hear the mitochondria referred to as the “powerhouse of the cell.”
Here's how the mitochondria is affected by red light:
LED light wavelengths from 600-800nm(red) and between 810-850nm(infrared) penetrate through the skin into the cells via a red light therapy device.
Light enters the cell's mitochondria, absorbed by chromophores which include EZ water and protein cytochrome c oxidase (CCO), resulting in stimulating activity.
Subsequently, three molecules are affected: Adenosine Triphosphate (ATP), Reactive Oxygen Species (ROS), and Nitric Oxide (NO).
Interestingly, our body weight is made of 70% water, with 99% of our bodies' molecules also made of water, making it a powerful component in red light therapy treatment.
Research by Prof Gerald Pollock of the University of Washington proved that water adjacent to a cell is structured water, also known as EZ water. This specific water forms a separation of charge, functioning in the body as positive and negative poles - similar to a battery.
What Does “Red Light Therapy” Mean?
While we’ve been talking about red light therapy, what does it actually mean? Typically, “red light therapy” refers to natural light treatments which deliver red and near-infrared wavelengths as natural sunlight using LEDs or cold lasers.
While you may think red light therapy includes all colors of light, it doesn’t. The term doesn’t include blue or white light, and it isn’t equivalent to full-spectrum light. Red light therapy doesn’t rely on heat, differentiating it from other light-based treatments such as infrared saunas and heat therapy.
Red light therapy is also known as RLT, photobiomodulation (PBM), phototherapy, LED therapy, LED light therapy, infrared therapy, low-level laser therapy, or low-level light therapy (LLLT).
Red Light Therapy: The Multilevel Treatment
As stated before, red light therapy works to heal the entire body and functions on multiple levels.
Adenosine triphosphate (ATP)
Retrograde mitochondrial signaling
Reactive oxygen species
Water, opsins, chromophores, cytochrome c oxidase
Gene transcription factors
Brain-derived neurotrophic factor
Inflammation, Cytoprotection, Proliferation
Stem cell production and migration
Immune cell viability
Retrograde mitochondrial signaling
Transforming growth factor
Pro-and anti-inflammatory cytokines
Mitochondrial membrane potential
Muscles: Increase endurance, tone density
Brain: Improves cognition and immune
Nerves: Repair and pain relief
Healing bones, tendons, and wounds
Increases hair growth
Improvement of the collagen network, anti-aging, skin disorders
Fat re-absorption improved by enhanced micro-circulation
Improved immunity and lymphatic system
Systemic Effects: Positive Affects on Bodily Systems
Red light therapy affects the body in multiple ways, including bodily systems:
Fascia is the thin casing of connective tissue that surrounds virtually every organ, muscle, nerve fiber, blood vessel, and bone in place. While it performs as an internal structure for your body, the fascia also contains nerves, making it almost as sensitive as skin.
The fascia may look like a layer of tissue; however, it’s made up of interwoven layers of collagen and elastin fibers. The fascia is overlooked, yet over recent years, it has been the key to understanding how changes in one area of our body affect others. Red light therapy works to improve communication within the fascia network.
The gut-brain axis connects the emotional and cognitive centers of the brain with peripheral intestinal functions. Recent research discovered the importance of gut microbiota concerning these interactions.
Red light therapy can positively influence mood and neuropsychological issues by the following:
Reducing gut spasms and bowel inflammation.
Increasing neurotransmitters, activating the brain’s immune system, thus increasing blood flow and eliminating toxins.
Reduce blood pressure and increase circulation to eliminate brain fog and anxiety.
Changes the vagus nerve, which connects the gut and brain. It plays a role in stress and social communication.
Changes of the micro-biome.
Red and near-infrared light penetrate through the skin into the cells, which results in low-dose metabolic stress that strengthens the cells’ anti-inflammatory and natural defense systems. In turn, the body becomes resilient to infections.
Safe and low exposure to red light therapy improves the body’s response to external viruses and bacteria. Red light therapy can influence the immune response in the following ways:
Enhances proliferation, maturation, and motility of fibroblasts.
Activates macrophages to behave as phagocytes.
Increases production of fibroblast growth.
Proliferation and activation of lymphocytes.
Release of pro-inflammatory cytokines and mast cell degranulation.
Activation of mast cells results in reduced inflammation.
Red light therapy is scientifically proven to increase the micro-circulation of blood and support the circulatory system as a whole by stimulating the development of new capillaries which carry oxygen throughout the body.
Proper oxygen supply and flow are essential for the proliferation of cells, protein synthesis, tissue restoration, inflammatory response, and angiogenesis. In addition, circulation is also responsible for waste elimination, specifically degenerated cells.
The nervous system includes the brain, spinal cord, neurons, and neural support cells, which is your body’s command center. It controls your movements, automatic responses, and other body systems such as digestion and breathing.
Red light therapy affects the nervous system in the following ways:
Releases growth factors.
Increases the vascular network and collagen.
Facilitates neural regeneration.
Regenerates the nerve lesions and damaged nerves at a faster rate.
Improves the electrophysiological function.
Myelination of fibers.
For all forms of nerve damage, red light therapy offers non-pharmaceutical treatment options.
Red light therapy shows impressive results regarding stem cell growth, maximizing the potential of stem cell implantation for various medical needs. Therefore, red light therapy may show positive results after surgery to stimulate stem cells which repair tissues and organs.
In studies, red light therapy has proven to stimulate mesenchymal stem cells in bone marrow, enhancing their ability to reach the brain. This research shows the possibilities of using red light therapy to heal degenerative conditions, including Alzheimer’s, Parkinson’s disease, and dementia.
The Origins of Modern Red Light Therapy
It’s clear red light therapy provides multilevel treatment to the body, becoming a popular natural and holistic option for both professionals and consumers, but where did it come from?
Light therapy technology isn’t new; it’s been around for decades as NASA experimented with red light therapy during the 1980s and 1990s. Over the past 10-20 years, red light therapy reached a breakthrough in LED lighting technology, allowing the production of safe and affordable clinical and at-home devices.
We mentioned red light therapy being a holistic treatment option, but what does that mean. Holistic medicine is a full-body approach to healthcare. By focusing on the body, mind, and soul, the body receives the full support and care it needs to function optimally.
Principles of Holistic Medicine
Holistic medicine is based on the following principles:
Optimal health is the combination of emotional, mental, spiritual, social and physical wellness.
The focus is to prevent first, and treat second.
The disease or illness is not caused by a single area, rather the whole body.
The purpose of treatment is to identify the underlying cause of the disease, rather than treating only the symptoms.
6 Main Benefits from Red Light Therapy
While there are endless benefits the body receives from red light therapy, here are the six main benefits.
Relieves Pain And Discomfort
Photobiomodulation, in other words, red light therapy, has proven effective against carpal tunnel syndrome, mucositis, neck pain, menstrual cramps, temporomandibular joint pain, and neuropathic pain from amputation. It also significantly reduces the pain of hypersensitivity while improving sensorimotor function.
These improvements come after anti-inflammatory cells populate the injured area, providing long-lasting pain relief. In addition, it’s also been shown to provide effective relief by affecting the following:
Represses cyclooxygenase and prostaglandins.
Activating peripheral opioid receptors.
Increasing endorphins serotonin release.
Stimulates the metabolism.
Changes nerve transmission.
Red light therapy has proven to be highly effective in rapidly treating wounds from burns, scars, bedsores, ulcers, surgery incisions, and diabetic neuropathy.
NASA strongly supports this claim as this technology was used in treating wounds. Red and near-infrared light proves effective in all four phases of the wound-healing process:
These processes are regulated by various factors connected via nitric oxide (NO) signaling release, adjusted by light energy.
An issue the body encounters when trying to heal a wound is low oxygen flow, and red light increases the flow of oxygen, speeding up the natural healing process. By reducing inflammation and increasing oxygenation of the wounded area, blood vessels can form, rapidly repairing the area, lessening pain and scarring.
By reducing pain, red light therapy eliminates the reliant on pharmaceutical painkillers during the healing process.
The human body receives energy on the cellular level, maintaining communication between organs and ensuring disease resistance.
A strong immune system works to protect the body from harmful bacteria and viruses at all times. With red light therapy, the body receives a boost of support as it releases nitric oxide and melatonin, two components involved in DNA repair and antimicrobial.
This process is called hormesis. Red and near-infrared wavelengths penetrate through the skin into the cells, causing mild metabolic stress, which stimulates cells to activate their anti-inflammatory and antioxidant response.
With the support of red light therapy, the body is better prepared to fight infections. Numerous studies have proven red light therapy to have the following effects on the immune system:
Improves melatonin production
Increases NO levels
Improves antioxidant production
Improves thyroid function
Stimulates T cells pre-operatively
Increases flow of neurotransmitters
Boosts collagen and elastin production
Encourages lymph node activity
Enables the transportation of immune cells
Stimulates optimal function of cells and organelles
Inflammation in the body can be acute and topical (short-term, resulting from sprains, infections, and accidents) or chronic and general (long-term, caused by ongoing conditions).
Acute inflammation is a healthy bodily response; however, chronic and general inflammation can negatively impact long-term health.
As of today, the current treatment for inflammation is NSAID or steroid drugs, both having a detrimental effect on the healing process and long-term health. Red light therapy stimulates the body to activate its natural healing mechanism, reducing the health risks of long-term drug use.
Red light therapy decreases the number of inflammatory cells, increases fibroblast proliferation (cells that synthesize collagen and other matrix macromolecules), stimulates angiogenesis (creation of new blood vessels), and activates the body’s anti-inflammatory, antioxidant response.
The following conditions are connected with chronic and acute inflammation, all proving promising results with red light therapy treatment:
Neuron inflammatory disorders such as Alzheimer’s
Irritable bowel syndrome and colitis
Red light therapy is extremely popular in competitive sports and performance. It offers natural and non-pharmaceutical treatment, which applies to many areas of the body.
Aside from the overwhelming benefits on overall health, red light therapy encourages muscles growth and repair by stimulating the production of ATP, which aids in faster recovery and better performance.
Red light therapy used before training prepares and strengthens the body while aiding muscle recovery after training.
Here are the scientifically documented effects of red light therapy:
Reducing DOMS (Delayed Onset Muscle Soreness)
Enhanced endurance and performance
Increasing sleep quality
Improving sexual function and libido (including Testosterone)
Aiding weight loss
Boosting cognitive function
Reversing skin aging
Reduces symptoms of depression and seasonal affective disorder
Seasonal affective disorder (SAD) is a form of depressions, impacting 5% of Americans, specifically during the winter when there’s less natural sunlight. SAD is also known as seasonal depression or winter blues.
Many people treat SAD symptoms via bright white light treatment, mimicking the sun’s light daily. However, researchers recommend natural light treatment, like red light therapy, to help with light deficiency. Over recent years, physicians recommend red light therapy alongside psychotherapy and medication.
Who Can Use Red Light Therapy?
While many people are using red light therapy devices for at-home treatment, red light therapy systems are found in many clinical and professional settings:
Skincare Professionals: Red light therapy is a popular skincare treatment among Hollywood celebrities, including Kourtney Kardashian, Julia Roberts, and Emma Stone. Leading skincare professionals like dermatologists and aestheticians use red light therapy to help promote collagen production, reduce wrinkles, and treat skin conditions.
Health Practitioners: Health practitioners from all specialties are incorporating red light therapy into their practice. Dentists use it to reduce inflammation, physicians for mental health conditions, and oncologists for cancer side effects.
Natural Health Experts: Leading voices in the health and wellness industry such as Dr. Sarah Ballantyne, Ben Greenfield, and Dave Asprey strongly support the use of red light therapy. Paleo and Keto health experts like Robb Wolf, Mark Sisson, Luke Story, and Dr. Anthony Gustin also support red light therapy.
Sports Medicine Pros: The National Sports Association of Sports Medicine (NASM) adopted red light therapy to treat sports injuries. Top trainers and doctors, including Dr. Troy Van Biezen and Dr. Ara Suppiah, use red light therapy to heal their athletes.
Elite Pro Athletes: Professional athletes worldwide, including NFL stars like Patrick Peterson, UFC champion Anthony Pettis, and gold medal gymnast Sanne Weavers use red light therapy to enhance performance and quicken recovery.
Fitness & Training: World-renown fitness trainers, including Lacey Stone and Jorge Cruise, use red light therapy to enhance athletic performance and muscle recovery.
Supportive Cancer Care: The Multinational Association of Supportive Care in Cancer (MASCC) recommends the treatment of red light therapy for oral mucositis (OM), a common symptom of cancer treatment.
Sources and References:
Klepeis N., Nelson W., Ott W., Robinson J., Tsang A., Switzer P., Behar J., Hern S., Engelmann W. “The National Human Activity Pattern Survey (NHAPS): a resource for assessing exposure to environmental pollutants”. Journal of Exposure Analysis and Environmental Epidemiology 2001.
Hamblin M. “Mechanisms and applications of the anti-inflammatory effects of photobiomodulation.” AIMS Biophys. 2017.
LED Lights Used in Plant Growth Experiments for Deep Space Missions. NASA.
Gál P, Stausholm MB, et al. Should open excisions and sutured incisions be treated differently? A review and meta-analysis of animal wound models following low-level laser therapy. Lasers in Medical Science. 2018 Aug.
John Foley, David B Vasily, et al. 830 nm light-emitting diode (led) phototherapy significantly reduced return-to-play in injured university athletes: a pilot study. Laser Therapy. 2016 Mar.
Kim HK, Choi JH. Effects of radiofrequency, electroacupuncture, and low-level laser therapy on the wrinkles and moisture content of the forehead, eyes, and cheek. Journal of Physical Therapy Science. 2017 February.
Wunsch A and Matuschka K. A Controlled Trial to Determine the Efficacy of Red and Near-Infrared Light Treatment in Patient Satisfaction, Reduction of Fine Lines, Wrinkles, Skin Roughness, and Intradermal Collagen Density Increase. Photomedicine and Laser Surgery. Feb 2014.
Barolet D, Roberge CJ, et al. Regulation of skin collagen metabolism in vitro using a pulsed 660 nm LED light source: clinical correlation with a single-blinded study. Journal of Investigative Dermatology. 2009 December.
Morita T., Tokura H. “ Effects of lights of different color temperature on the nocturnal changes in core temperature and melatonin in humans” Journal of Physiological Anthropology. 1996, Sept.
Naeser M., Zafonte R, Krengel MH, Martin PI, Frazier J, Hamblin MR, Knight JA, Meehan WP, Baker EH. “Significant improvements in cognitive performance post-transcranial, red/near-infrared light-emitting diode treatments in chronic, mild traumatic brain injury: open-protocol study” Journal of Neurotrauma. 2014, June.
Liu KH, Liu D, et al. “Comparative effectiveness of low-level laser therapy for adult androgenic alopecia: a system review and meta-analysis of randomized controlled trials.” Lasers in Medical Science. 2019 Aug.
Gupta AK, Mays RR, et al. “Efficacy of non-surgical treatments for androgenetic alopecia: a systematic review and network meta-analysis.” JEADV. 2018 Dec.
Afifi L, Maranda EL, et al. “Low-level laser therapy as a treatment for androgenetic alopecia.” Lasers in Surgery and Medicine. 2017 Jan.
Hofling DB, Chavantes MC, et al. Low-level laser in the treatment of patients with hypothyroidism induced by chronic autoimmune thyroiditis: a randomized, placebo-controlled clinical trial. Lasers in Surgery and Medicine. May 2013.
Hofling DB, Chavantes MC, et al. Assessment of the effects of low-level laser therapy on the thyroid vascularization of patients with autoimmune hypothyroidism by color Doppler ultrasound. ISRN Endocrinology. 2012.
Hofling DB, Chavantes MC, et al. Low-level laser therapy in chronic autoimmune thyroiditis: a pilot study. Lasers in Surgery and Medicine. 2010 Aug.
Vladimirovich Moskvin S., Ivanovich Apolikhin O. Effectiveness of low level laser therapy for treating male infertility. Biomedicine (Taipei). 2018 June.
Ban Frangez H., Frangez I., Verdenik I., Jansa V., Virant Klun I. Photobiomodulation with light-emitting diodes improves sperm motility in men with asthenozoospermia. Laser in Medical Science, 2015 Jan.
Salman Yazdi, R., Bakhshi, S., Jannat Alipoor, F. et al. Effect of 830-nm diode laser irradiation on human sperm motility. Lasers Med Sci. 2014.
Chow KW, Preece D, Burns MW. Effect of red light on optically trapped spermatozoa. Biomedical Optics Express. 2017 Aug.
Preece D., Chow KW, Gomez-Godinez V., Gustafson K., et al. Red light improves spermatozoa motility and does not induce oxidative DNA damage. Scientific Reports. 2017 Apr.
American Psychiatric Association
Cassano P, Petrie SR, et al. Transcranial Photobiomodulation for the Treatment of Major Depressive Disorder. The ELATED-2 Pilot Trial. Photomedicine and Laser Surgery. 2018 October.
Barrett DW, et al. Transcranial infrared laser stimulation produces beneficial cognitive and emotional effects in humans. 2013 Jan.
Blanco NJ, Maddox WT, Gonzalez-Lima F. Improving executive function using transcranial infrared laser stimulation. Journal of Neuropsychology. 2017 Mar.
Paolillo FR, Borghi-Silva A, et al. New treatment of cellulite with infrared-LED illumination applied during high-intensity treadmill training. J Cosmet Laser Ther. 2011 Aug;13(4):166-71.
Caruso-Davis MK, Guillot TS, Podichetty VK, Mashtalir N, Dhurandhar NV, Dubuisson O, Yu Y. Efficacy of low-level laser therapy for body contouring and spot fat reduction. Obes Surg. 2011. Jun;21(6):722-9.
Jackson RF, Dedo DD, Roche GC, et al. Low-level laser therapy as a non-invasive approach for body contouring: a randomized, controlled study. Lasers in Surgery and Medicine. Dec 2009;41(10):99-809.
McRae E and Boris J. Independent evaluation of low-level laser therapy at 635 nm for non-invasive body contouring of the waist, hips, and thighs. Lasers in Surgery and Medicine. Jan 2013.
Avci P, Gupta A, et al. Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring. Seminars in Cutaneous Medicine and Surgery. Mar 2013; 32(1): 41-52.
Based on Washington Post, an estimated 20.3% of Americans (50 million) experience chronic pain, making it seem as if it’s a part of being alive. And while we’ve grown to accept the fact we’ll experience pain at some point, we rarely realize the negative impact pain can have physically and mentally. When ignored or mistreated, acute pain can manifest into chronic pain, bringing along a series of adverse long-term effects. This can create a cycle of pain and can immensely affect one’s ability to use the area in pain. Chronic pain can also develop many health issues, including high blood pressure, fatigue, sleeping problems, and even eating disorders.
When we talk about pain relief, it’s mandatory to bring up pain medications. While this type of pain relief is tempting because of its convenience, it can bring further health complications. Low-risk drugs such as ibuprofen may be harmless at first, but overuse can have adverse health consequences. And opioids are proven to lose effectiveness long-term, making them highly addictive. But then, “how do we manage pain safely and effectively?” One option is the holistic method of red light therapy.
The Light Spectrum
To understand red/infrared treatment clearly, one must first understand what the light spectrum is and how it works. The light spectrum visible to the human eye is just a portion of the entire electromagnetic spectrum. Our eyesight is only able to see wavelengths from 380 to 700 nanometers. Nanometers are units of measurement which measure light. One nanometer equates to one billionth of a meter.
Humans can only see violet, blue, green, yellow, orange, and red colors on the light spectrum. Humans are not able to see infrared, which is measures in the mid-800s nanometer range. As objects become hotter, they produce more energy which is dominated by shorter wavelengths. Thus, changing colors before our eyes. Flames from a blow torch, for example, transform from red to blue as their temperature increases and wavelengths grow shorter.
Scientists use the light spectrum as a method for measuring the temperature of stars. Our sun produces more yellow light because it has a 5,500 C° temperature. If our sun were cooler, say 3,000 C°, it would have a reddish appearance. If it were 12,000 C°, it would appear to be blue.
One the light spectrum, blue light is measured at 400 to 500 nanometers. This type of light therapy is commonly used for bright light therapy (aka phototherapy). It’s proven to increase alertness, memory, and moods. It’s beneficial for turning off melatonin production to make us feel more alert. It should be noted that too much blue light can cause sleep disorders. It’s recommended to limit electronic usage at night because they emit blue light.
When it comes to blue light therapy, it’s best to proceed with caution. Due to its lower wavelengths and higher energy levels, blue light can cause eye damage. Studies have shown light colors between 415 and 455 nanometers to cause harm to the eyes — standard electronics including TVs, computers, and cell phones produce wavelengths from 400 to 490 nanometers. Additional research is needed to understand the long-term effects.
Red and Infrared Light
In comparison to blue light, red light is on the opposite end of the spectrum. Red light is delivered in the mid-600 nanometer range, while infrared is in the mid-800s. Due to its range and longer wavelengths, infrared is invisible to the human eye.
Red and infrared light, commonly used to treat skin and pain conditions, have been proven to be a holistic treatment for:
Increasing injury recovery time
These types of light are effective because of their ability to penetrate deep into the skin. Red and infrared light promotes melatonin production. This stimulates the production of adenosine triphosphate (ATP). ATP is essential to function properly as it provides our body’s cells with energy. This is why red light therapy products are so effective for speeding up the healing process.
Red light therapy lights are effective because of their ability to reach deep into the skin without damaging it. Red light therapy machines penetrate 2–7 centimeters into inner skin layers using red and infrared light to effectively reach muscles, nerves, and bones. Wavelengths from 700 to 1,000 nanometers are ideal for treating inflammation conditions.
The warmth we feel from the sun is infrared light. Infrared light does not contain ultraviolet radiation, which is harmful to us. Once the skin is penetrated, red and infrared light becomes absorbed by photoreceptors in our body’s cells. This creates a series of metabolic events and natural processes within the cells. When our bodies are exposed to red light therapy, here’s what happens:
Cells receive a boost of energy: Once red light is absorbed, each cell’s mitochondria boost energy. Mitochondria, known as the powerhouse of the cell, is responsible for producing energy. Because their function is increased, mitochondria produce more adenosine triphosphate (ATP). ATP is an energy-carrying molecule found in the cells of all living things. When given more energy, cells can function correctly.
Cells repair and regenerate more quickly: Many experts believe that they gain an enhanced ability to repair and restore themselves because of excess energy from red light therapy. This creates healing in skin and muscle tissues. The quicker cells can regenerate and repair, the faster injuries heal.
Nitric oxide gets released: Nitric oxide is essential to healthy arteries. This gas helps arteries relax, reduces oxidative stress by fighting free radicals, prevents vessels from platelet clumping, and aids in blood pressure regulation. This allows the molecule to enhance blood circulation to deliver vital nutrients and oxygen to damaged tissues. This sparks the repair and regeneration of injured tissues, reducing pain and inflammation.
Collagen production is increased: The protein collagen provides structure to the skin. It’s also existent in muscle and connective tissue. When injuries heal, separated tissues are stitched back together through a latticework made up of collagen. Collagen production is increased when exposed to red and infrared light. Increased collagen production equated to healthier skin which is better able to heal effectively.
Stem cells become activated: Stem cells are where specialized cells such as brain cells, blood cells, heart muscle cells, and bone cells come from. When stem cells are exposed to red and infrared light, they become activated. They then travel through the bloodstream to the injured area. After arriving, they transform into the needed cell type to help with healing. One study found red and infrared light effectively activates stem cells in the bone marrow. Thus, assisting in the healing process.
When it comes to how red light therapy works and improves our body’s functions, it’s pretty complex. There is still much research required to understand how it works fully, its benefits, and the long-term effects. Yet, our current knowledge shows a promising future for pain relief and holistic health.
Type of Pain Treated by Red Light Therapy
Red light therapy has clinically proven to be versatile for treating many pain types, including chronic, joint, neck, osteoarthritis, and more. Because it provides targeted pain relief, it’s incredibly versatile for various conditions. We’ve provided a list of the many pain types red light therapy helps, along with studies.
Because of its general safety, red light therapy can be used at home or anywhere it’s needed. It’s excellent for anyone with chronic pain and can be used as often as it’s needed, up to three times per day per target area.
A study on elderly patients with osteoarthritis in their knees (joints) found red light therapy to treat their pain and disability.
Red light therapy for neck pain is an effective treatment for chronic pain in the neck. One study involving 60 students with chronic neck pain found red light therapy an effective pain relief method. In six weeks, red light therapy increased range of motion, decreased pain, and improved functionality.
By nature, osteoarthritis causes inflammation in affected areas. This makes red light therapy an excellent treatment for osteoarthritis. A study that compared high-intensity light therapy to low-intensity light therapy found both effective decreasing pain and improving function when combined with exercise.
Red light therapy enhances the healing process by boosting the body to lower swelling in target areas. Chiropractors use red light therapy to treat bursitis because it effectively treats this condition.
Healthline reports red light therapy as an effective short-term method for carpal tunnel relief. However, these studies are limited.
45 patients with diabetic foot ulcers, in a study, reported improved blood circulation and autonomous nervous system regulation after using red light therapy.
A study conducted in 2011 on patients with psoriasis compared red and blue light therapy’s effectiveness. Participants were given high-dose treatments three times each week for four hours, applying 10% silicic acid solution to plaques. The study concluded both are effective in treating psoriasis.
It’s been shown that red light therapy reduces pain and stiffness associated with rheumatoid arthritis. Healthcare professionals are now starting to study and consistently use red light therapy to diagnose and analyze this condition. Red light therapy gives them the ability to see how much light passes through the body. RA often alters the number of tissues, water, and blood in the affected area. Red light gives doctors an insight into how it’s progressing.
When treating ailments, red and infrared therapy offers a drug-free, safe, and effective relief method. Extensive studies on red light therapy show it a great source of foot pain relief, back pain relief, and more. As studies move forward, we’ll continue to gain a fuller understanding of red LED light therapy, its capabilities, and the conditions it can treat.
Injuries & Recovery Time
When it comes to recovery for athletes, red light therapy has made significant strides. During the Rio Olympics, the US track team was spotted bringing a $181,000 red light therapy bed to the event. Micheal Hamblin, a Harvard expert, stated, “red light therapy may help you recover from exercise, sleep better, heal wounds and injuries like tendonitis, reduce arthritis.” What’s more, a study involving 65 athletes with varying strains, sprains, tendonitis, ligament damage, and contusions found red light therapy to reduce the average return to play period. This treatment was able to reduce the average recovery time from 19.23 to 9.6 days.
Rats with Osteoporosis experienced enhanced bone repair and growth via red light therapy. This was achieved through stimulation of the newly formed bone, fibro vascularization, and angiogenesis.
With more than 15 years in the light industry, we can help you develop a light therapy device for all the conditions described above.
The first formal description of Seasonal Affective Disorder (SAD), the most well-known psychiatric condition associated with seasonality in humans, was introduced in the mid-1980s by Rosenthal, who described a group of 29 patients living in a temperate climate who experienced depressive episodes characterized by hypersomnia, hyperphagia, and weight gain in the fall or winter, and whose symptoms remitted by the next spring or summer.
SAD was incorporated into the Diagnostic and Statistical Manual (DSM) of Mental Disorders III-R when “seasonal pattern” was introduced as a specifier for Major Depression and Bipolar Disorders. Subsequent revision in DSM-IV described SAD as “a regular temporal relationship between the onset of Major Depressive Episodes in Bipolar I (BPI) or Bipolar II (BPII) Disorder or Major Depressive Disorder (MDD), recurrent, and a particular time of the year.”
Today, SAD, or MDD with seasonal pattern, is defined as recurrent episodes of major depression that meet the following criteria: at least two consecutive years where the onset and offset of depressive symptoms occur at characteristic times with no non-seasonal episodes, a temporal relationship between onset of symptoms and time of year, a temporal relationship between remission of symptoms and time of year, and an outnumbering of seasonal compared to non-seasonal episodes throughout the lifetime of the patient.
Pathophysiology of SAD
To date, the pathophysiology of SAD is unclear. Early research into the mechanism of SAD focused on day length or photoperiod. This hypothesis posited that shorter days in winter, possibly mediated by a longer duration of nocturnal melatonin secretion, leads to depressed mood in susceptible individuals. To date, there is little data to support this hypothesis. Furthermore, given that bright light in the evening has not been as effective as that given in the morning, it now seems unlikely that the photoperiod is the underlying pathological mechanism of SAD.
A circadian rhythm refers to the approximately 24-hour cycle of physiological processes present in humans and other animals. This cycle is governed via clock gene expression by the suprachiasmatic nucleus (SCN), the master pacemaker located within the anterior hypothalamus. Though the SCN endogenously generates circadian oscillations, SCN endogenously generates circadian oscillations, and they need to be entrained to the 24-hour day by external cues. Light exposure is the most important synchronizing agent of endogenous circadian rhythms.
Downstream of the SCN, a collection of systemically active neurohumoral networks transduce circadian information to the rest of the body. For instance, via projections to the hypothalamus's paraventricular nucleus, the activation of the SCN leads to autonomic changes, including cardiovascular modulation, and together the central, peripheral, and autonomic nervous systems collaborate to affect systemic changes. Thus, the SCN receives information about the external day-night cycle directly through retinofugal pathways and indirectly through neuromodulatory signaling. Circadian information is then relayed systemically through neurohumoral networks.
The current primary hypothesis for the pathophysiology of SAD, known as the “phase-shift hypothesis,” posits that there is an optimal relationship in the alignment of the sleep-wake cycle and the endogenous circadian rhythm. During the fall and winter, as day length shortens, the circadian rhythm begins to drift later concerning clock time and the sleep-wake cycle. This phase delay is hypothesized to bring about mood symptoms. A pulse of morning bright light generates a circadian phase advance, which is thought to correct the discordance between sleep and circadian phase, thereby ameliorating depressive symptoms. However, the phase-shift hypothesis would predict that the amount of phase correction required for each patient would depend on an individual’s PAD, which has not yet been proven.
Several studies have also proposed that serotonin is implicated in the pathophysiology of SAD, as selective serotonin reuptake inhibitors (SSRIs) appear to be effective in the treatment of SAD. Supporting this hypothesis, one study used Positron Emission Tomography (PET) imaging to look at binding probability at synaptic serotonin transporters in 88 normal individuals living in the temperate climate of Toronto, Canada (Praschak-Rieder, Willeit, Wilson, Houle, & Meyer, 2008). The binding probability was increased during fall and winter compared to warmer months, thus eliciting an inverse correlation between binding potential and sunlight durationsunlight duration. Of note, the largest difference in transporter binding was found in the mesencephalon, a finding consistent with animal studies demonstrating the importance of direct effects of light to the midbrain on behavior. If increased transporter activity indicated greater reuptake of serotonin during the fall/winter, and if this resulted in a lower density of cleft serotonin, then the seasonal variation in transporter activity (i.e., higher transporter efficiency in the winter) would seem to leave susceptible individuals particularly prone to mood symptoms during the darker seasons. Moreover, following BLT and during periods of remission in the summer months, the synaptic transporter activity was shown to be reduced to control levels in these patients.
BLT has also been investigated to a lesser extent in eating disorders. Because binge eating episodes have been observed to increase in fall and winter in some patients, BLT has been examined as a treatment modality for anorexia nervosa (AN) and bulimia nervosa (BN). Thus, BLT's effects on patients with eating disorders remain enigmatic. Additional studies, including larger, randomized, blinded, and controlled trials, are needed to elucidate further the role of BLT in treating this patient population. Further research might also determine whether BLT would be a useful treatment in Binge-Eating Disorder, a diagnosis new to DSM-5.
Additionally, BLT has been studied in the context of adult Attention-Deficit/Hyperactivity Disorder (ADHD), where, in addition to normal ADHD symptoms, patients often have depressed mood and difficulties falling asleep, awakening on time, and maintaining arousal (Brown & McMullen, 2001). These symptoms are indicative of a possible delay in the circadian rhythm. A case report of symptom improvement following BLT in a child with ADHD who displayed signs of delayed sleep phase also supports the idea that BLT may be useful in treating symptoms of ADHD (Gruber, Grizenko, & Joober, 2007). Whether the pathways that subserve the improvement of mood symptoms in response to BLT are the same pathways that underlie the seemingly beneficial effects of BLT in ADHD remains to be studied. While these results are promising, further studies, preferably in randomized, blinded, and controlled studies will need to be performed.
A significant immediate reduction of depression scores with light treatment can be identified after 20 minutes and reaches the maximum at 40 minutes, with no additional benefit at 60 minutes. The rate of change is steepest during the first 20 minutes of light as compared with longer intervals. Comparing the clinical impact of these durations of administration may yield different results when measured after several daily sessions. The overnight effect on circadian rhythms and sleep was not assessed in our study and is thought to impact mood regulation in SAD. Larger, prospective, controlled, and hypothesis-driven studies in more naturalistic conditions would be desirable to replicate our study results and our study results and analyze the temporal dynamic of the persistence of the immediate mood-improvement effects. Besides, in larger samples, one could define early responders and nonresponders, analyze genetic (e.g., melanopsin related genes), demographic (children, adolescents, adults, elderly, gender), physiological (e.g., pupillary responses), and clinical (e.g., abundant atypical symptoms) predictors for early response. If proven effective and efficacious, shorter exposures to bright light could become a feasible and broadly employed intervention for immediate mood improvement as an early step on the road toward full antidepressant response and remission.