Heat can transform in (3) Three different ways:

Heat transfers from high temperature to low. This is a basic principle. There are three (3) methods (conduction, convection and radiation) how the heat can transfer. Heat transfer is usually performed by a combination of these three methods.

Heat transfer by conduction: Heat gradually comes when one end of the iron bar is heated and becomes hot to the end. It is called conduction heat transfer that heat is transmitted through the material in this way. Thermal conductivities are different by a material. Metal is a good conductor of the heat. Gas is generally a low heat conduction body. Therefore, heat conduction becomes lower in the material with many apertures.

Heat transfer by convection: When liquid and gas, such as water and air, are heated from the bottom, the warmed part rises because its density lightens by expanding. On the other hand, the cold upper part drops. These actions are performed repeatedly, and total temperature rises. This kind of heat transferring method by moving liquid and gas is called convection.

Heat transfer by radiation: Heat transfer methods that do not need a medium, are called radiation heat transfer, as solar heat directly arrives at the earth and warms the ground. The heat is directly absorbed into a material in the form of electromagnetic waves and the temperature of the material raises (radiation activates the vibration of material atoms). Heat transfer by far-infrared rays is based on the radiation heat transferring itself.

Far-Infrared (Heat)

“Radiant heat” is neither ultraviolet radiation nor atomic radiation. “Radiant heat” is a form of energy that heats objects directly through a process called “conversion” without having to heat the air in between. ”Radiant heat” is also known as infrared energy (IR). Thermal radiation propagates without the presence of matter through the vacuum of space. The warming effect in the heaters that use far-infrared (FIR) technology is based specifically on radiation and not on conduction. In everyday life thermal radiation can be sensed well in sunny weather. In the sunlight it is warmer than in the shade, but the air has the same temperature in both cases.

The infrared segment of the electromagnetic spectrum is divided into three segments by wavelength, measured in microns or micrometers (a micron = 1/1,000,000 meter);

.76-1.5 microns = near or close (NIR).
1.5-5.6 = middle or intermediate.
5.6-1000 = far or long-wave infrared (FIR).

The infrared segment of the electromagnetic spectrum occurs just below or “infra” to red light as the next lowest energy band of light. This band of light is not visible to human eyes but can be seen by special cameras that translate infrared into colors visible to our eyes. However, we feel this type of light, perceived as heat.

The sun creates most of its energy within the infrared segment of the spectrum. Our atmosphere has a “window” in it that allows far-infrared (FIR) rays in the 7-14 microns or 7000-14000nm range to safely reach the earth’s surface. When warmed, the earth radiates infrared rays in the 7000-14000nm band and has a peak output at 10000nm’s.

The infrared heat in a greenhouse is just like the heat from our sun or that which our own bodies produce as they burn fuel to keep us warm. Supposedly, bodily tissues needing a boost in their output selectively absorb FIR rays. The internal production of infrared energy that normally occurs within our tissues is associated with a variety of healing processes. After boosting a tissue’s level to maximum, the remaining rays pass onward harmlessly. This phenomenon is called “resonant absorption.”

630nm Wavelength (Red Light)

The 630nm wavelength is ideal for targeting all manner of skin concerns. 630nm wavelengths penetrate into the skin cells and sebaceous (oil) glands to rejuvenate the skin’s tone and texture by smoothing and evening out uneven pigmentation.  This wavelength has also been found to help reduce the appearance of fine lines and wrinkles, and can also stimulate hair regrowth. 

Some of the diverse benefits of 630nm light include::

• Reduced fine lines and wrinkles: In one study, the 630nm wavelength was combined with other beauty treatments such as microneedling to create a statistically significant improvement in photodamage, fine lines and sagging.
• An improvement in skin disorders such as psoriasis: One study showed that the use of the 630nm wavelength used in conjunction with hematoporphyrin derivative (HPD) helped to eradicate the symptoms associated with psoriasis within 17 days.
• Hair regrowth: Red light therapy containing the 630nm wavelength has been proven to be a safe and effective method of stimulating hair growth in both men and women. One study hypothesized that the light stimulated stem cells in the hair follicle, encouraging the hair follicle into an anagen or growth phase.
• Healing of superficial skin cancers: Wavelengths of 630nm have been shown to help in the treatment of non-melanoma skin cancers.
• The treatment of acne: The 630nm wavelength has also been shown to help reduce inflammation and breakouts.

Joovv – 660nm Wavelength (Red Light)

There is an abundance of literature outlining the benefits offered by the 660nm wavelength. Penetrating just a little deeper than the 630nm wavelength, the 660nm reaches into the entire range of the skin tissue to promote healing and regeneration.

Some of the diverse benefits of 660nm light include:

• Reduced training fatigue: The 660nm wavelength teamed with the 830nm near-infrared wavelength has been proven to delay the development of fatigue in the muscles, and enhance skeletal muscle performance. (Athletes, take note.)
• Reduced inflammation: In a study investigating the effects of red light therapy on pleurisy, the 660nm wavelength was found to induce an anti-inflammatory effect. 
• Improved bone healing: The 660nm wavelength encourages resorption and formation in the bone cells around the location where repair is needed, without causing any change to the bone structure.
• Reduced swelling following injury: In one study, the 660 nm wavelength was found to reduce both inflammation and swelling by reducing the number of inflammatory cells which lead to the formation of swelling.
• Reduced neuropathic pain: A study investigating sciatic nerve pain in rats found that the 660 nm wavelength significantly helped to reduce pain.
• Accelerated wound healing: The 660 nm wavelength has been proven to increase the formation of new blood vessels and enhance collagen deposition to help in the healing of wounds.

810nm Wavelength (Near-Infrared Light)

With an ability to extend through the skull into the brain, the 810nm wavelength offers a unique array of neurological benefits. Many forward-thinking scientists are of the belief that light therapy for brain disorders will become a prominent medical treatment in the near future. Expect to reap the following benefits from the 810nm wavelength:

Some of its diverse benefits of 810nm light include:

• Improved healing and recovery: A study of soccer players showed that the 810nm wavelength applied before activity enhanced muscular performance and post-exercise recovery.
• Accelerated wound healing: 810nm wavelengths have been shown to help expedite wound healing, helping the tissue to granulate more rapidly.
• Improved recovery from stroke in certain patients: One study conducted among stroke patients showed that wavelengths of 810nm provided neuroprotective benefits and improved recovery among sufferers of moderate to severe strokes. Five days after the stroke, there was significant improvement among those who had been treated with the 810nm light therapy, compared to those who hadn’t. Ninety days post-stroke, 70% of the treated patients had a successful outcome, compared with only 51% of the control group.
• Improved recovery from traumatic brain injury: 810nm has been proven in animal models to be particularly effective in fostering recovery from traumatic brain injuries, and reducing long-term neurological damage.
• Improvement in psychiatric disorders: Prescription drugs for psychiatric conditions have long been recognized as having a limited ability to assist individuals suffering from psychiatric conditions. What’s more, pharmacotherapeutic medication often carries a host of unwanted side effects, while near-infrared light therapy doesn’t. 810nm wavelengths applied to the forehead have been shown to assist patients suffering from major depression and anxiety.
• Hair growth: Studies have shown the 810nm wavelength can encourage significant hair growth in patients with androgenetic alopecia.

830nm Wavelength (Near-Infrared Light)

The 830nm wavelength is not as readily absorbed by the body, therefore it is able to penetrate deeper through skin and tissue and into the bone. A greater quantity of photons is delivered into the tissue with the 830nm wavelength. 

Some of its diverse benefits of 660nm light include:

• Accelerated healing and reduced infection: Like the 810nm wavelength, 830nm accelerates healing in wounds of different severity and helps to ward off infection.
• Improved aesthetic outcomes following plastic surgery: Swift exposure to 830nm wavelengths after aesthetic surgery hastens recovery, reduces downtime and enhances the results of surgery by reducing swelling, infection, bruising and pain, therefore leading to greater patient satisfaction.
• Increased “feel-good” endorphins: 830nm wavelengths increases the release of endorphins. Endorphins are peptides which promote feelings of wellness and provide a natural analgesic, triggering a sensation similar to morphine.
• Improved bone repair and growth: An animal study demonstrated that 830nm light therapy improved bone repair by stimulating new bone growth.
• Faster return-to-play after injury: The ability to return-to-play as swiftly as possible after injury or trauma is a key concern for any amateur or professional athlete. 830nm LED light therapy has been proven to significantly and safely reduce the wait time before injured athletes can return to play.

Joovv – 850nm Wavelength (Near-Infrared Light)

Some of the diverse benefits of 850nm light include:

• Anti-inflammatory benefits: 850nm wavelengths can help to reduce joint and muscle pain and diminish general inflammation in the body.
• Enhanced muscle recovery: A study observed the use of 850nm wavelengths on athletes, and found that usage of the near-infrared light increased muscle mass after training, and decreased inflammation and oxidative stress in muscle biopsies.
• Healing of wounds in the skin: Lesions in the skin heal faster when exposed to 850nm wavelength light therapy.
• Reduction of lines, wrinkles, and hyperpigmentation: 850nm can support the production of collagen, assisting with plumper, more radiant-looking skin, and a more uniform texture.
• Orthodontics and tooth alignment: The use of the 850nm wavelength can foster the speedy realignment of teeth for patients undergoing orthodontics.

Additional data on photobiomodulation and the benefits of red and near-infrared light

Psychological benefits – NIR-PBM may have utility for the treatment of depression and other psychiatric disorders.

Everything You Need To Know About Red Light Therapy

Infrared and skin: Friend or foe – In the last decade, it has been proposed that the sun’s IR-A wavelengths might be deleterious to human skin and that sunscreens, in addition to their desired effect to protect against UV-B and UV-A, should also protect against IR-A (and perhaps even visible light). Several studies showed that NIR may damage skin collagen content via an increase in MMP-1 activity in the same manner as is known for UVR. Unfortunately, the artificial NIR light sources used in such studies were not representative of the solar irradiance. Yet, little has been said about the other side of the coin. This article will focus on key information suggesting that IR-A may be more beneficial than deleterious when the skin is exposed to the appropriate irradiance/dose of IR-A radiation similar to daily sun exposure received by people in real life. IR-A might even precondition the skin – a process called photoprevention – from an evolutionary standpoint since exposure to early morning IR-A wavelengths in sunlight may ready the skin for the coming mid-day deleterious UVR. Consequently, IR-A appears to be the solution, not the problem. It does more good than bad for the skin. It is essentially a question of intensity and how we can learn from the sun.

Near-infrared light increases ATP, extends lifespan and improves mobility in aged Drosophila melanogaster – Aging is an irreversible cellular decline partly driven by failing mitochondrial integrity. Mitochondria accumulate DNA mutations and reduce ATP production necessary for cellular metabolism. This is associated with inflammation. Near-infrared exposure increases retinal ATP in old mice via cytochrome c oxidase absorption and reduces inflammation. Here, we expose fruit flies daily to 670 nm radiation, revealing elevated ATP and reduced inflammation with age. Critically, there was a significant increase in average lifespan: 100–175% more flies survived into old age following 670 nm exposure and these had significantly improved mobility. This may be a simple route to extending lifespan and improving function in old age.

Turning On Lights to Stop Neurodegeneration: The Potential of Near Infrared Light Therapy in Alzheimer’s and Parkinson’s Disease – Red to infrared light therapy (λ = 600–1070 nm), and in particular light in the near-infrared (NIr) range, is emerging as a safe and effective therapy that is capable of arresting neuronal death. Previous studies have used NIr to treat tissue stressed by hypoxia, toxic insult, genetic mutation and mitochondrial dysfunction with much success.

2017 – Mechanisms and applications of the anti-inflammatory effects of photobiomodulation – Great data on PBM. This paper was stated that cytochrome c oxidase was the primary light receptor. The paper below proved it was actually the mitochondrial matrix water.

Mechanisms and Mitochondrial Redox Signaling in Photobiomodulation – This review will cover the redox signaling that occurs in PBM and examine the difference between healthy and stressed cells, where PBM can have apparently opposite effects. PBM has a marked effect on stem cells, and this is proposed to operate via mitochondrial redox signaling. PBM can act as a pre-conditioning regimen, and can interact with exercise on muscles.

2019 – Mitochondrial cytochrome c oxidase is not the primary acceptor for near-infrared light—it is mitochondrial bound water: the principles of low-level light therapy – There is substantial evidence that various wavelengths of light, including R-NIR delivered by lasers or LEDs are instrumental in upregulating mitochondrial ATP levels. Conflicting data cast serious doubt on the validity of the concept that CCO is the primary photoacceptor for R-NIR light being causal for the ATP upregulation. At the same time there is conclusive evidence that both ATP upregulation and cell proliferation by R-NIR light occurs via the interaction of photons with intracellular IWL.

Avoidance of sun exposure as a risk factor for major causes of death: a competing risk analysis of the Melanoma in Southern Sweden cohort. – Women with active sunlight exposure habits experience a lower mortality rate than women who avoid sun exposure; however, they are at an increased risk of skin cancer. 

Photobiomodulation for Alzheimer’s Disease: Has the Light Dawned? – Next to cancer, Alzheimer’s disease (AD) and dementia is probably the most worrying health problem facing the Western world today. A large number of clinical trials have failed to show any benefit of the tested drugs in stabilizing or reversing the steady decline in cognitive function that is suffered by dementia patients. Although the pathological features of AD consisting of beta-amyloid plaques and tau tangles are well established, considerable debate exists concerning the genetic or lifestyle factors that predispose individuals to developing dementia. Photobiomodulation (PBM) describes the therapeutic use of red or near-infrared light to stimulate healing, relieve pain and inflammation, and prevent tissue from dying. In recent years PBM has been applied for a diverse range of brain disorders, frequently applied in a non-invasive manner by shining light on the head (transcranial PBM).

Proposed chromophores for PBM that can absorb different wavelengths of light. It should be noted that there is considerable overlap between the chromophores, and that the NIR absorbed by structured water is likely to be longer wavelength (>950 nm).

Is It Time to Consider Photobiomodulation As a Drug Equivalent? One of the impressive and perspective challenges for photobiomodulation is its use in cases of Parkinson’s disease. Research in recent years evidenced that neuroprotective treatment with red and near infrared radiation (NIR) prevented mitochondrial dysfunction and dopamine loss in Parkinson’s disease patients. Another development in recent years is the successful stimulation of stem cells with red and NIR radiation. Photobiomodulation has been shown to improve functional outcome after surgical intervention to repair injured nerves…

Protection against neurodegeneration with low-dose methylene blue and near-infrared light While low-dose methylene blue and low-level near-infrared light may produce different pleiotropic cellular effects, both interventions cause a similar up-regulation of mitochondrial respiration with similar benefits to protect nerve cells against degeneration. First, both interventions increase the expression of brain cytochrome oxidase in vivo (Gonzalez-Lima et al., 2014). Methylene blue accomplishes this by supporting the electron transport chain, while near-infrared light does it by directly energizing cytochrome oxidase via photon absorption ​(Figure1). Still, their primary cellular mechanism of action is the same: enhancement of mitochondrial respiration.

(Fig. 1) Two neuroprotective interventions for enhancing mitochondrial respiration. Low-dose methylene blue (MB) acts as an exogenous electron (e-) cycler, boosting oxygen consumption and cell respiration (molecular O2 reduced to H2O). Low-level red-to-near-infrared light directly energizes cytochrome oxidase (Complex IV) via photon absorption, facilitating its catalytic activity and leading to up-regulation of cytochrome oxidase levels. These interventions result in long-term increases in the amount of cytochrome oxidase in the electron transport chain by a process of enzymatic induction, which promotes oxidative energy metabolism and neuronal survival. Abbreviations: I–IV, refer to the four electron transport enzymatic complexes in the inner membrane of mitochondria; MB, is oxidized methylene blue (blue color); MBH2, is reduced methylene blue (colorless); H+, stands for the protons pumped by Complexes I, III, and IV that enter the mitochondrial matrix via ATP synthase, which results in ATP production. Also see: Methylene Blue as a Cerebral Metabolic and Hemodynamic Enhancer

The effect of red-to-near-infrared (R/NIR) irradiation on inflammatory processes.

DISCUSSION: The effects that R/NIR may induce in immune cells typically involve the production of reactive oxygen species (ROS), nitrogen oxide (NO), or interleukins. Production of ROS after exposure to R/NIR can either be inhibited or to some extent increased, which suggests that detailed conditions of experiments, such as the spectrum of radiation, irradiance, exposure time, determine the outcome of the treatment. However, a wide range of immune cell studies have demonstrated that exposure to R/NIR most often has an anti-inflammatory effect. Finally, photobiomodulation molecular mechanism with particular attention to the role of interfacial water structure changes for cell physiology and regulation of the inflammatory process was described.

CONCLUSIONS: Optimization of light parameters allows R/NIR to act as an anti-inflammatory agent in a wide range of medical applications.