The quick answer is no, sunscreen doesn’t block infrared light, and you don’t need to block it.
The wavelengths of UV coming from the sun are classified as UV-A (320–400 nm), UV-B (290–320 nm), and UV-C (100–290 nm). UV-C has the highest energy, making it the most dangerous of the three-wavelength types. Luckily, the earth’s ozone layer protects UV-C (light that is even higher energy than UV is absorbed by nitrogen in the atmosphere), leaving UV-A and UV-B wavelengths to be of concern. The high energy of photons of UV light can penetrate the skin and trigger damaging reactions within the skin’s DNA or excite other chromophores present in the skin to form reactive oxygen species (ROS).
Ninety-five percent of UV radiation that reaches the earth’s surface is UV-A radiation. UV-A radiation triggers the tanning reactions in the skin, as the skin darkens in an attempt to protect itself from further damage. UV-A plays a major role in skin aging. It also causes damage to the epidermis (the outermost layer of the skin) and is a factor in developing skin cancers.
Wavelength: 320–400 nm.
Effects: Tanning, Premature skin aging, Skin cancer.
Protection: Avobenzone (Parsol 1789), Ecamsul (Mexoryl), Zinc oxide.
Wavelength: 290–320 nm.
Effects: Vitamin D production, Sunburn, Cataracts, Genetic damage, Skin cancer.
Protection: Oxybenzone, Homosalate, Octinoxate, Octisalate, Titanium dioxide.
Wavelength: 100–290 nm
Effects: Cellular decomposition
Protection: Ozone in the lower stratosphere
A sunscreen product’s efficacy is commonly indicated by its “sun protection factor” or SPF. The SPF indicates how long it will take for UV-B rays to begin to redden the skin. Skin coated with an SPF 15 sunscreen will take 15 times longer to redden than without the sunscreen.
Infrared waves, or infrared light, are part of the electromagnetic spectrum. People encounter Infrared waves every day; the human eye cannot see them, but humans can detect them as heat. The remote control uses light waves beyond the visible spectrum of light — infrared light waves — to change channels on your TV.
Sunscreens do not shield skin from any infrared rays. Topical antioxidants should help shield the skin. Ignore the chatter about infrared. Ignore the sunscreens which claim to block infrared.
Focus on protecting your skin from UVA and UVB using a broad-spectrum sunscreen and physically keeping the sun off your skin with clothing, a hat, and shade. Yes, wear UPF 50 clothing and a sun hat when outdoors. Head for the shade or create it. Apply mineral zinc oxide-based sunscreen to exposed skin not covered by UV-blocking clothing. There is no controversy with these recommendations, and your skin will look great and stay strong for your lifetime if you protect it from UV exposure.
Daniel Barolet, François Christiaens, and Michael R Hamblin, Infrared and Skin: Friend or Foe, J Photochem Photobiol B. J Photochem Photobiol B. 2016 Feb; 155: 78–85.
Laura Hudson Eyman Rashdan Catherine A. Bonn Bhaven Chavan David Rawlings Mark A. Birch‐Machin, Individual and combined effects of the infrared, visible, and ultraviolet light components of solar radiation on damage biomarkers in human skin cells, The FASEB Journal, Volume34, Issue3, March 2020, 3874–3883 https://doi.org/10.1096/fj.201902351RR
Chronic nonspecific back pain (CNBP) is a common and cost-intensive musculoskeletal syndrome in Western society. This condition is the most common cause of disability in North America, and it accounts for 64% of new consultations at this pain clinic. It has a lifetime prevalence of up to 80%, and for example, in low back pain, high rates of repeated occurrence have been reported. The mechanisms underlying CNBP are manifold: Mechanical reasons are not the sole triggers, as it was demonstrated that 85% of all CNBP cases show no morphologic causes. There is international consensus that comorbidities such as mood and anxiety disorders are associated with higher levels of perceived pain, and psychosocial mechanisms are essential in the chronification of pain. Patients suffering from depression with comorbid pain show longer times to remission. Psychosocial factors such as avoidance behavior and anxiety are closely connected to depression. They are evidently more accurate predictors for the development of chronic pain compared with biographical or somatic determinants. It has been reported that 60% of chronic pain patients show manifest symptoms of depression. The prevalence of depression is three to four times higher in low back pain patients than in the general population.
Pain relief with IR has been shown and studied for arthritis of the knee. Other beneficial effects documented are increased wound healing, blood flow, endorphin levels, and bioactivation of neuromodulators.
Infrared light promotes faster healing of deep tissues by penetrating the skin and improving the circulation of oxygenated blood in the body, thus relieving pain. Infrared light therapy can penetrate deeply so that it can help even harder to reach cells and tissues.
When infrared light reaches the smallest unit in our body, which are the cells, it is absorbed by the power generators of the cell, which are called mitochondria. This increases the cell’s metabolism, stimulating healing in the muscle, bone, skin, and subcutaneous tissue.
Improving the metabolism of the cells will increase blood flow. A vital component for this is the release of nitric oxide, a molecule that signals the blood flow when activated. Increased blood flow helps bring oxygenated blood and nutrients to different parts of the body, most especially to areas where there is pain. Aside from that, increased blood flow also paves the way for body wastes to be drained from the body faster. All these are crucial in the healing process, which reduces the inflammation and pain of the affected area.
It is widely accepted that a multimodal approach is required in the treatment of CNBP. The incorporation of infrared light therapy may offer this combined intervention strategy — considering pain, psychosocial, and emotional factors and being cost-effective. Infrared light therapy has proved successful mainly in the treatment of mood disorders. It has also been of interest in the treatment of various other behavioral syndromes such as eating and circadian rhythm disorders and headaches. That infrared light therapy could effectively treat CNBP can most likely be explained by the fact that pain and depression have been shown to share similarities in pathophysiological pathways and the brain regions affected. Additionally, melatonin, which strongly depends on the light-dark cycle, contributes to pain control through antinociceptive activity on spinal and supraspinal levels. In fact, MT1 and MT2 melatonergic receptors play an essential role in pain regulation by reducing hyperalgesia and modulating inflammation.
The frequency of sessions will depend on your alignment and the severity. Clients with chronic pain who have regular weekly sessions find this helps manage their ongoing pain issues by staying ahead of the inflammation and helps proactively manage their pain. If the pain is temporary, then 2–3 sessions may be what you need.
If you are unsure, discuss your needs with our friendly staff, who will help you sort through what’s right for your needs.
Restless legs syndrome (RLS) is a condition that causes an uncontrollable urge to move your legs, usually because of an uncomfortable sensation. It typically happens in the evening or nighttime hours when you’re sitting or lying down. Moving eases the unpleasant feeling temporarily. Doctors think RLS may be worsened by microvascular problems. This means that there is not enough blood flow and oxygen getting to these parts of the body.
Near-infrared (NIR) light is one therapy being used to help oxygenate tissues and treat RLS.
Near-infrared (NIR) is the region closest in wavelength to the radiation detectable by the human eye. Mid-and far-infrared is progressively further from the visible spectrum. NIR light therapy uses light to bring oxygen to tissues. Small sticky pads or a handheld light-emitting device are placed on your legs. Light of a particular wavelength passes from the patches or device through your skin. NIR light aims to increase blood flow. The extra oxygen that comes with the blood could help control your RLS symptoms.
A lack of blood flow could be a reason for bad symptoms. The body normally pumps blood and fresh oxygen to all its tissues. If there is not enough oxygen, the tissue becomes hypoxic. Hypoxic tissues may feel numb or tingly, and they may hurt.
If hypoxia in the legs and feet causes bad symptoms, then getting more oxygen to the tissues can bring relief. This can be done by getting the body’s blood vessels to vasodilate or enlarge. Bigger blood vessels bring more blood and oxygen to tissues.
NIR light therapy is called phototherapy, meaning it uses light as a treatment. Doctors think the NIR light enlarges blood vessels enough to raise the oxygen levels in the legs and feet.
NIR light therapy exposes your legs and feet to NIR light several times a week for many weeks. The light is delivered through patches that stick to your skin or through holding a small device against your leg.
For phototherapy, light passes through your skin either through sticky patches or a handheld device. Both are safe. There may be a little warming of the skin while the light is on, but this is not harmful.
A 2011 study, among others, showed that NIR light therapy lessened RLS symptoms after only 2 weeks. More research is needed to figure out if NIR light therapy works better on primary or secondary RLS and if it works better on males or females.
A 69-year-old Caucasian woman met International Restless Legs Syndrome Study Group criteria to diagnose restless legs syndrome. She had been afflicted with restless legs syndrome for over 30 years and tried many available pharmaceutical remedies without success. For this study, she received 30-minute treatment sessions with near-infrared light three times a week for four weeks. The restless legs syndrome rating scale was used to track symptom changes; at baseline, she scored “27” on the 0 to 40 point scale, which is considered “severe.” The patient was almost symptom-free at week two, indicated by a score of “2” on the rating scale. By week four, she was completely symptom-free.
Phototherapy increases endorphins. These endorphins are the same “feel good” chemicals your brain makes when you exercise. Endorphins relieve pain which could be another benefit to NIR light therapy.
Mitchell, U.H. Use of near-infrared light to reduce symptoms associated with restless legs syndrome in a woman: a case report. J Med Case Reports 4, 286 (2010). https://doi.org/10.1186/1752-1947-4-286
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6108511/
Researchers at NCI’s Center for Cancer Research have found that a technique called near-infrared immunotherapy for treating cancer has the potential to kill cancer cells in record time, essentially destroying them with the flick of a light switch. Scientists were not certain of the underlying mechanisms of this approach. Still, they succeeded in elucidating this technique in detail at the cellular and molecular level, gaining insights that could help scientists further boost the novel treatment's effectiveness. The laboratory and mouse findings, by Hisataka Kobayashi, M.D., Ph.D., Senior Investigator in the Molecular Imaging Program, and colleagues appeared November 6, 2018, in ACS Central Science.
Near-infrared immunology is an emerging technique for treating cancer that is already being studied in clinical trials. It involves identifying a protein called an antibody that recognizes and targets a specific type of cancer cell. The antibody is joined to a compound that’s sensitive to light and then administered to a patient. Within the body, the drug seeks out and attaches to only cancer cells, not healthy ones. Next, doctors apply a beam of infrared light to the cancer site, either externally or directly, using a fiber optic needle, which activates the drug and causes them to die. Research by Dr. Kobayashi and his colleagues reveals new details into how this cell death occurs.
To learn more about this phenomenon's molecular mechanisms, they studied the effects of a near-infrared immunotherapy agent called antibody-IR700 on a plate simulating human cancer cells in a petri dish using sophisticated microscopes. The researchers discovered that exposure to near-infrared light causes the immunotherapy agent to change its form from Y-shaped to globular dramatically. When it is embedded in a cancer cell's cell membrane, this warping causes scratches along the cell's protective casing. Once enough scratches occur, liquid bursts through the cell’s membrane, causing the cell to rupture in less than a minute following exposure to the light.
The researchers also studied this technique in a mouse with multiple tumors, applying different light intensity amounts to each tumor. They found that higher light intensity resulted in more cancer cells being eliminated. In mice, they detected the “leftovers” of the immunotherapy agent in the mouse’s urine just hours after near-infrared light was applied to the cancer site — a strong indication that the cancer cells were killed.
Dr. Kobayashi notes that this technique doesn’t just target cancer cells or boost the immune system to attack cancer cells — it does both. “All the cell’s proteins and even its DNA are exposed to the immune system. The immune system will recognize that [the proteins and DNA are] coming from the dying cell, and then the immune system will react only to the dying cancer cells,” he explains.
Near-infrared immunotherapy could be applied to any cancer if the right antibody is identified and used. In this study, the researchers analyzed the near-infrared immunotherapy agent IR-700, which is about to be tested in phase III clinical trials for head and neck cancer.
Although the concept of near-infrared immunotherapy is compelling, understanding why it works is critical for several reasons. Kobayashi explains, “Based on these new insights, we might be able to design a new, superior IR700 that would be improved in many respects, such as activation wavelength, stability, and cytotoxic efficacy.”
Destroying cancer cells without damaging normal cells nor compromising the host immune system is a significant benefit of NIR-PIT. Additionally, NIR-PIT induces ICD; that is, it initiates host immunity against targeted cancer cells. NIR-PIT-treated cancer cells release death signals, including calreticulin, ATP, and HMGB1, which can activate adjacent immature DCs even in tumor beds. These signals promote the maturation of immature DCs, which engulf cancer-specific antigens that are released from the ruptured tumor cell, and these mature DCs prime and educate naive T cells to become cancer-specific CD8+ T cells. Such newly primed cancer-specific CD8+ T cells proliferate and attack other cancer cells, resulting in an amplified host anti-tumor immune response. This consequential process could convert some non-immunogenic tumors into immunogenic tumors by recognizing massively released neo-antigens.
This anti-tumor immune activation occurs first in the treated tumor site. Eventually, it extends to other cancer sites because immune cells migrate throughout the body, resulting in a systemic immune response. Therefore, although NIR-PIT is a local therapy, the effect of NIR-PIT can be systemic and may affect distant metastatic sites. Indeed, some tumor-bearing mice and cancer patients achieve complete remission after a single therapy of cancer-cell-targeted NIR-PIT.
An important feature of host immune activation induced by NIR-PIT is that this therapy simultaneously activates the immune system against multiple antigens released from ruptured cancer cells. Most current targeted immunotherapies, including cancer vaccines or CAR-T therapies, identify a single target molecule to base the therapy. Having multiple clones of anti-tumor T cells, each responding to unique antigen, results in a more comprehensive response to tumors expressing a broad spectrum of cancer-specific neo-antigens.
NIR-PIT has demonstrated a profound immune response in humans. First-in-human Phase 1 and Phase 2 clinical trials of NIR-PIT with cetuximab–IR700 targeting EGFR in patients with recurrent and advanced head and neck squamous cell cancer were completed in 2016 and late 2017, respectively. Several complete remissions and multiple significant partial remissions were reported in these studies. The results far exceeded those of pre-clinical models in immune-deficient host xenograft models. Once the models were transferred to syngeneic models, a robust immune response was demonstrated. There is considerable evidence that this same response is seen in humans.
The control of fire by early humans was a turning point in the technological evolution of human beings. Fire provided a source of warmth, protection from predators, a way to create more advanced hunting tools, and a method for cooking food. These cultural advances allowed human geographic dispersal, cultural innovations, and changes to diet and behavior. Additionally, creating fire allowed human activity to continue into the evening's dark and colder hours.
Claims for the earliest definitive evidence of fire control by a member of Homo range from 1.7 to 2.0 million years ago. Evidence for the “microscopic traces of wood ash” as the controlled use of fire by Homo erectus, beginning some 1,000,000 years ago, has wide scholarly support. Flint blades burned in fires roughly 300,000 years ago were found near fossils of early but not entirely modern Homo sapiens in Morocco.
The fire was used regularly and systematically by early modern humans to heat treat silcrete stone to increase its flake-ability for toolmaking approximately 164,000 years ago at the South African site of Pinnacle Point.[5] Evidence of widespread control of fire by anatomically modern humans dates to approximately 125,000 years ago.They also used fire for light.
The burning of wood (or other organic materials) releases energy in the form of infrared light. When you take a photo of someone with an infrared camera, what do you see? A heat “signature” that correlates (approximately) to their metabolic activity.
What is infrared light? It is a spectrum of light that we can’t see but that powerfully shapes our biology. You sense infrared light as “heat.” The heat you feel from the sun — that’s the sensation of infrared light. The feeling of heat you get when you put your hand close to an oven, toaster, or fire — that is also infrared light. The heat of another person’s body — infrared light again. Hot springs transfer heat to your body in the form of infrared light stored in the water itself. When you take a hot shower or hot bath, the same principle is at work.
Infrared light has been used for decades as a heat source for saunas. Before IR saunas, we had sweat lodges and traditional stone saunas. In traditional saunas and sweat lodges, stones absorb energy from either an electronic heating unit (in the case of a sauna) or a fire. The light is stored in the stones and gradually released during the sweat lodge or the sauna. Both methods use light to heal the human body.
And infrared light doesn’t just transfer “heat” to your body — it turns the water in your cells into batteries. This is likely why ancient cultures recognize the importance of fire, sweat lodges, and saunas, especially in winter.
It is not a coincidence that sitting down next to a fire is so comfortable. Firelight is natural and helps to manage melatonin production as well as keeping our circadian rhythms under control.
A fireplace or fire-pit isn’t just an ornamental detail of your home, and it’s a tool you can use to live a healthier life.
