October 2025

Utilizing Near Infrared Light for Therapeutic Treatment of Cancer

Natural light in all its forms is essential to the health and vitality of the human body. In addition to setting the circadian rhythm, signals from sunlight received both through the eyes and on the skin produce necessary hormones, neurotransmitters, and other significant molecules such as nitric oxide and Vitamin D. Circadian alignment supports more than the sleep/wake cycle, it also controls the timing and tuning of metabolic processes and the rest and recovery all organ systems. Visible light is electromagnetic radiation detectable by the human eye, while ultraviolet and infrared light are forms of electromagnetic radiation just outside of the visible range of the spectrum. Humans and other organisms evolved in the presence of all three forms of light, as well as other natural electromagnetic fields which are discussed in another bulletin. These adaptations were fine-tuned by evolution, leading to complex systems in the animal body designed to harvest light for a variety of purposes, including ‘seeing’ the immediate environment (visible light), producing vitamin D (UVB light), and managing daily metabolic cycles (orchestrated through circadian cycles that involve the production of circulating and subcellular melatonin). The elucidation of these processes has led us to an understanding of the importance of circadian alignment in cancer prevention and overall health.

Infrared light, which comprises 50% of incident light on the earth’s surface, is lower in energy than the visible and ultraviolet light. Near Infrared light (NIR) by convention refers to that portion of the spectrum ranging from ca. 700nm-1,400nm. NIR has been studied by many investigators to answer questions about the way it interacts with biological systems (reviewed in Tanaka and Gale 2013 and Arranz-Paraiso et al 2023). Some answers have been forthcoming. For example, NIR has been shown to affect mitochondrial function in cultured cardiomyocytes (heart muscle cells) (Zhang et al 2009, from an LED array with peak emission at 670nm) and microglial cells (immune cells that reside in the brain) in Alzheimer’s mouse models (Stepanov et al 2022, laser diode emitting at 808 nm), switching cells from lactate (fermentative) to a healthier oxidative metabolism. Columbo et al (2021) review the literature reporting effects of NIR on endothelial function, citing positive effects in re-vascularization and endothelial function. Because of provocative results with many disease conditions in animal models and cell culture, there has been much interest in understanding the potential therapeutic effects of NIR exposure in humans and their domestic animals, especially in cancer prevention and treatment.

Historically, the connection between natural sunlight deprivation and cancer was noticed over a hundred years ago by Hoffman (1915) who observed that indoor workers had an 8-fold higher risk of dying of cancer. Vitamin D, synthesized in the animal body in the presence of UVB light, is now known to be effective in improving cancer survival outcomes and mitigating adverse reactions, but this information has been slow to percolate into the medical establishment.  Grant (2019) addresses structural aspects of our system to explain why physicians continue to reject supplemental vitamin D use in cancer treatment regimens despite the fact that medical researchers have clearly established the anti-cancer effects of vitamin D in cancer treatment paradigms. While the anti-cancer effect of vitamin D is important, emerging understanding of the anti-cancer properties of melatonin (which is also light dependent) as well as of direct interactions between NIR and cellular stress pathways (mitochondrial and extra-mitochondrial) suggests that NIR light itself might have direct anti-tumor effects. The direct effect of light on cells to influence cell division and viability is referred to in the technical literature as either photobiomodulation or low-level laser therapy. Most of the published literature on the subject of photobiomodulation and cancer reports that low level NIR treatment causes cessation of cell division (senescence) or cell death (apoptosis) in cancer tissues but not in normal tissues.

Early studies using NIR to eliminate tumors were provocative (McGuff et al 1965; Kozlov et al 1973; reviewed in Hamblin et al 2018), and more recently, a significant number of studies report positive effects of NIR in cultured tumor cells or tumors in vivo (in a living organism). For example, Kalampouka (2024) showed in well-controlled experiments that NIR induced non-reversible senescence in cultured MCF7 breast cancer and lung cancer A549 cells but not in normal counterparts treated in parallel (LED array (734 nm)). The treatments were observed to increase reactive oxygen species (ROS), alter Calcium balances, and disturb the membrane potential of the mitochondria from treated tumor cells, suggesting that the mitochondrial effects were at least partially involved in halting cell division. Antunes et al (2017) describe a Phase III head and neck cancer trial in which significantly improved outcomes were observed with NIR treatment (referred to as low level laser therapy in their study, which used an InGaAlP diode emitting at 660nm with 100mW-1J-4J/cm). Hamblin and Liebert (2022) discuss the fact that although the mitochondria are clearly involved in the range of anti-tumor effects, there are other cellular targets besides the mitochondrion. Ravera and colleagues (2021) describe the use of an 808nm NIR laser (0.25-1.25 W) to study mitochondrial responses in squamous cell carcinoma line (OHSU-974 FAcorr). The NIR treatments induced apoptosis and senescence in those cells.

The promise of positive outcomes in cell lines and cancer patients has been tempered by a small number of studies suggesting that NIR at certain wavelengths and high fluence (laser energy per unit area) levels might actually increase the rate of cell division in some cases (reviewed in Hamblin et al 2018), including melanoma cells in vitro (in cell culture) and in mice (Frigo et al 2009). This last study contrasts with the earlier study in mice (referred to above - Kozlov et al 1973) that reported tumoricidal (tumor killing) effects of high dose NIR therapy in a mouse melanoma model. Without analyzing the technical differences between those two studies in detail, suffice it to say that these opposing results appear to be caused by differences in wavelength, dose, and irradiance, as well as in the details of the cancerous tissues used in the models (discussed in Kalampouka et al 2024; Hamblin and Liebert 2022). In addition, and importantly when thinking about the possibility of using NIR treatment for a cancer, there is a large body of experimental work using red light (630 nm, 650mn) and NIR light at 810 nm to activate tumoricidal chemicals in pre-clinical trials (see among many others, Chan et al 2017, Kobayashi and Choyke 2019, Wang et al 2020,nag et al 2020, and Chen et al 2025), suggesting that those wavelengths and fluences are safe. Penetration into tissues is also a consideration when choosing a treatment regime – some experimental work has been done on this front (Henderson and Morries 2015; Koster 2022; Hendersen 2024; Woo 2025). Overall, the take home message is that some care should be taken in the choice of dose, duration of exposure, and wavelength, and that ideally treatment should be initiated in consultation with a provider who is experienced in the use of NIR. Also bear in mind that this discussion refers to the therapeutic use of NIR light as a treatment for cancer, not its value as part of the natural light spectrum that is necessary for maintaining overall health and vitality.

Hamblin and Liebert (2022) also point out that despite the fact that there have been hundreds of small-scale animal and human studies demonstrating therapeutic effects of NIR in many pathological conditions, including cancer, this significant body of promising preliminary evidence has led to no large-scale trials or sponsorship by the medical establishment. One can’t help but wonder why this is. Hamblin and Liebert partially attribute it to the fact that the cellular effector mechanisms are not well understood, but the same could be said of many of the pharmaceutical agents currently in use. It seems to us that dominance of the pharmaceutical industry has had a role in this situation. This leads us to the final question, is NIR worth using in the self-treatment setting? The evidence accumulated to date is highly suggestive, and with very low numbers of reported adverse effects, low to moderate doses of NIR in general seem to be at the very least harmless and at the most actually helpful in eliminating tumors. And, for a number of reasons, supplementing any treatment program with natural sunlight is also clearly a good option – imagine taking sick leave to read a book in the sun! Note that when utilizing artificial light sources, we recommend checking the manufacturing background of the devices and purchasing from trusted suppliers who report consistency of light wavelengths in the product and reduced electromagnetic outputs of the device itself.

Antunes, H. S., Herchenhorn, D., Small, I. A., Araujo, C. M., Viégas, C. M. P., de Assis Ramos, G., ... & Ferreira, C. G. (2017). Long-term survival of a randomized phase III trial of head and neck cancer patients receiving concurrent chemoradiation therapy with or without low-level laser therapy (LLLT) to prevent oral mucositis. Oral oncology, 71, 11-15.

Arranz-Paraíso, D., Sola, Y., Baeza-Moyano, D., Benitez-Martinez, M., Melero-Tur, S., & González-Lezcano, R. A. (2023). Mitochondria and light: An overview of the pathways triggered in skin and retina with incident infrared radiation. Journal of Photochemistry and Photobiology B: Biology, 238, 112614.

Chan, M. H., Pan, Y. T., Lee, I. J., Chen, C. W., Chan, Y. C., Hsiao, M., ... & Liu, R. S. (2017). Minimizing the heat effect of photodynamic therapy based on inorganic nanocomposites mediated by 808 nm near‐infrared light. Small, 13(21), 1700038.

Chen, H., Zhao, X., Halimov, A., Fu, M., Tu, J., Liu, H., ... & Liu, J. (2025). Phototheranostic Zinc Porphyrin Nanoparticles Triggered by an 808 nm Laser: NIR-II Fluorescence/Photoacoustic Imaging-Guided Combined Photothermal/Photodynamic/NO Therapy. Bioconjugate Chemistry, 36(4), 838-845.

Colombo, E., Signore, A., Aicardi, S., Zekiy, A., Utyuzh, A., Benedicenti, S., & Amaroli, A. (2021). Experimental and clinical applications of red and near-infrared photobiomodulation on endothelial dysfunction: A review. Biomedicines, 9(3), 274.

Frigo, L., Luppi, J. S., Favero, G. M., Maria, D. A., Penna, S. C., Bjordal, J. M., ... & Lopes-Martins, R. A. (2009). The effect of low-level laser irradiation (In-Ga-Al-AsP-660 nm) on melanoma in vitro and in vivo. BMC cancer, 9(1), 404.

Grant, W. B. (2019). Vitamin D Reduces Cancer Risk: Why Scientists Accept It but Physicians Do Not. Orthomedicine News Release.

Hamblin, M. R., Nelson, S. T., & Strahan, J. R. (2018). Photobiomodulation and cancer: what is the truth?. Photomedicine and laser surgery, 36(5), 241-245.

Hamblin, M. R., & Liebert, A. (2022). Photobiomodulation therapy mechanisms beyond cytochrome c oxidase. Photobiomodulation, Photomedicine, and Laser Surgery, 40(2), 75-77.

Henderson, T. A., & Morries, L. D. (2015). Near-infrared photonic energy penetration: can infrared phototherapy effectively reach the human brain?. Neuropsychiatric disease and treatment, 2191-2208.

Henderson, T. A. (2024). Can infrared light really be doing what we claim it is doing? Infrared light penetration principles, practices, and limitations. Frontiers in Neurology, 15, 1398894.

Hoffman F: The Mortality of Cancer throughout the World. Appendix E, Prudential Press, 1915.

Holick, M. F. (2016). Biological effects of sunlight, ultraviolet radiation, visible light, infrared radiation and vitamin D for health. Anticancer research, 36(3), 1345-1356.

Kalampouka, I., Mould, R. R., Botchway, S. W., Mackenzie, A. M., Nunn, A. V., Thomas, E. L., & Bell, J. D. (2024). Selective induction of senescence in cancer cells through near‐infrared light treatment via mitochondrial modulation. Journal of Biophotonics, 17(8), e202400046.

Kobayashi, H., & Choyke, P. L. (2019). Near-infrared photoimmunotherapy of cancer. Accounts of chemical research, 52(8), 2332-2339.

Koster, P. M. (2022). Near Infrared Light Penetration in Human Tissue: An Analysis of Tissue Structure and Heterogeneities. Marquette University.

McGuff, P. E., Deterling Jr, R. A., & Gottlieb, L. S. (1965). Tumoricidal effect of laser energy on experimental and human malignant tumors. New England Journal of Medicine, 273(9), 490-492.

Mumtaz, S., Rana, J. N., Choi, E. H., & Han, I. (2022). Microwave radiation and the brain: Mechanisms, current status, and future prospects. International journal of molecular sciences, 23(16), 9288.

Ravera, S., Bertola, N., Pasquale, C., Bruno, S., Benedicenti, S., Ferrando, S., & Amaroli, A. (2021). 808-nm photobiomodulation affects the viability of a head and neck squamous carcinoma cellular model, acting on energy metabolism and oxidative stress production. Biomedicines, 9(11), 1717.

Stepanov, Y. V., Golovynska, I., Zhang, R., Golovynskyi, S., Stepanova, L. I., Gorbach, O., ... & Qu, J. (2022). Near-infrared light reduces β-amyloid-stimulated microglial toxicity and enhances survival of neurons: Mechanisms of light therapy for Alzheimer’s disease. Alzheimer's research & therapy, 14(1), 84.

Tanaka, Yohei, and Lisa Gale. "Beneficial applications and deleterious effects of near-infrared from biological and medical perspectives." Optics and Photonics Journal 3, no. 4 (2013): 31-39.

Wang, Q., Xu, J., Geng, R., Cai, J., Li, J., Xie, C., ... & Fan, Q. (2020). High performance one-for-all phototheranostics: NIR-II fluorescence imaging guided mitochondria-targeting phototherapy with a single-dose injection and 808 nm laser irradiation. Biomaterials, 231, 119671.

Woo, K. (2025). Unraveling the role of photobiomodulation in tumor biology and therapy. Medical Lasers; Engineering, Basic Research, and Clinical Application, 14(1), 1-8.

Yang, J., Hou, M., Sun, W., Wu, Q., Xu, J., Xiong, L., ... & Zhang, C. (2020). Sequential PDT and PTT using dual‐modal single‐walled carbon nanohorns synergistically promote systemic immune responses against tumor metastasis and relapse. Advanced Science, 7(16), 2001088.

Zhang, R., Mio, Y., Pratt, P. F., Lohr, N., Warltier, D. C., Whelan, H. T., ... & Bienengraeber, M. (2009). Near infrared light protects cardiomyocytes from hypoxia and reoxygenation injury by a nitric oxide dependent mechanism. Journal of molecular and cellular cardiology, 46(1), 4-14.