In a recent post we explained one of the scientific theories for how red light therapy improves the health of your skin.
In this article, we’d like to point you to 6 clinical studies that clearly demonstrate the anti-aging benefits of red light therapy. So if you’re feeling studious, let’s dive in…
A prospective, randomized, placebo-controlled, double-blinded, and split-face clinical study on LED phototherapy for skin rejuvenation: clinical, profilometric, histologic, ultrastructural, and biochemical evaluations and comparison of three different treatment settings
SOURCE: J Photochem Photobiol B. 2007 Jul 27;88(1):51-67. Epub 2007 May 1
BACKGROUND: Light-emitting diodes (LEDs) are considered to be effective in skin rejuvenation.
OBJECTIVE: We investigated the clinical efficacy of LED phototherapy for skin rejuvenation through the comparison of three different treatment parameters and a control, and also examined the LED-induced histological, ultrastructural, and biochemical changes.
METHODS: Seventy-six patients with facial wrinkles were treated with quasimonochromatic LED devices on the right half of their faces. All subjects were randomly divided into four groups treated with either 830nm alone, 633nm alone, a combination of 830 and 633nm, or a sham treatment light, twice a week for four weeks. Serial photography, profilometry, and objective measurements of the skin elasticity and melanin were performed during the treatment period with a three-month follow-up period. The subject’s and investigator’s assessments were double-blinded. Skin specimens were evaluated for the histologic and ultrastructural changes, alteration in the status of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), and the changes in the mRNA levels of IL-1ss, TNF-alpha, ICAM-1, IL-6 and connexin 43 (Cx43), by utilizing specific stains, TEM, immunohistochemistry, and real-time RT-PCR, respectively.
RESULTS: Objectively measured data showed significant reductions of wrinkles (maximum: 36%) and increases of skin elasticity (maximum: 19%) compared to baseline on the treated face in the three treatment groups. Histologically, a marked increase in the amount of collagen and elastic fibers in all treatment groups was observed. Ultrastructural examination demonstrated highly activated fibroblasts, surrounded by abundant elastic and collagen fibers. Immunohistochemistry showed an increase of TIMP-1 and 2. RT-PCR results showed the mRNA levels of IL-1ss, TNF-alpha, ICAM-1, and Cx43 increased after LED phototherapy whereas that of IL-6 decreased.
CONCLUSION: This therapy was well-tolerated by all patients with no adverse effects. We concluded that 830 and 633nm LED phototherapy is an effective approach for skin rejuvenation.
The use of light-emitting diode therapy in the treatment of photoaged skin
SOURCE: J Cosmet Dermatol. 2007 Sep;6(3):189-94
BACKGROUND: Light-emitting diode (LED) therapy is an increasingly popular methodology for the treatment of sun damage. Combination use of light wavelengths reported to stimulate collagen synthesis and accelerate fibroblast-myofibroblast transformation may display a composite rejuvenative effect.
OBJECTIVE: To clinically assess reduction in sun damage signs following a 5-week course of LED therapy and to assess subject’s perception of the treatment.
METHODS: Thirteen subjects with wrinkles or fine lines in the periorbital and nasolabial region and those presenting Glogau scale photodamage grade II-III received nine 20-min duration light treatments using the Omnilux LED system. The treatments combined wavelengths of 633 and 830 nm at fluences of 126 and 66 J/cm(2), respectively. Sun-damage reduction was assessed at 6, 9, and 12 weeks by clinical photography and patient satisfaction scores.
RESULTS: The majority of subjects displayed “moderate” (50%) or “slight” (25%) response to treatment at investigator assessment. Treatment of the periorbital region was reported more effective than the nasolabial region. At 12-week follow-up, 91% of subjects reported improved skin tone, and 82% reported enhanced smoothness of skin in the treatment area.
CONCLUSION: Good response to LED therapy has been shown in this modest sample. Larger trials are needed to assess optimum frequency of light treatments and overall treatment time.
Regulation of skin collagen metabolism in virtro using a pulsed 660 nm LED light source: clinical correlation with a single-blinded study
SOURCE: J Invest Dermatol. 2009 Dec;129(12):2751-9. doi: 10.1038/jid.2009.186. Epub 2009 Jul 9
BACKGROUND: It has been reported that skin aging is associated with a downregulation in collagen synthesis and an elevation in matrix metalloproteinase (MMP) expression.
OBJECTIVE: This study investigated the potential of light-emitting diode (LED) treatments with a 660 nm sequentially pulsed illumination formula in the photobiomodulation of these molecules.
METHODS: Histological and biochemical changes were first evaluated in a tissue-engineered Human Reconstructed Skin (HRS) model after 11 sham or LED light treatments. LED effects were then assessed in aged/photoaged individuals in a split-face single-blinded study.
RESULTS: Results yielded a mean percent difference between LED-treated and non-LED-treated HRS of 31% in levels of type-1 procollagen and of -18% in MMP-1. No histological changes were observed. Furthermore, profilometry quantification revealed that more than 90% of individuals showed a reduction in rhytid depth and surface roughness, and, via a blinded clinical assessment, that 87% experienced a reduction in the Fitzpatrick wrinkling severity score after 12 LED treatments. No adverse events or downtime were reported.
CONCLUSION: Our study showed that LED therapy reversed collagen downregulation and MMP-1 upregulation. This could explain the improvements in skin appearance observed in LED-treated individuals. These findings suggest that LED at 660 nm is a safe and effective collagen-enhancement strategy.
Clinical experience with light-emitting diode (LED) photomodulation
SOURCE: Dermatol Surg. 2005 Sep;31(9 Pt 2):1199-205
BACKGROUND: Light-emitting diode (LED) photomodulation is a novel nonthermal technology used to modulate cellular activity with light.
OBJECTIVE: We describe our experience over the last 2 years using 590 nm LED photomodulation within a dermatologic surgery environment.
METHODS: Practical use of nonthermal light energy and emerging applications in 3,500 treatments delivered to 900 patients is detailed.
RESULTS: LED photomodulation has been used alone for skin rejuvenation in over 300 patients but has been effective in augmentation of results in 600 patients receiving concomitant nonablative thermal and vascular treatments such as intense pulsed light, pulsed dye laser, KTP and infrared lasers, radiofrequency energy, and ablative lasers.
CONCLUSION: LED photomodulation reverses signs of photoaging using a new nonthermal mechanism. The anti-inflammatory component of LED in combination with the cell regulatory component helps improve the outcome of other thermal-based rejuvenation treatments.
Green tea and red light: a powerful duo in skin rejuvenation
SOURCE: Photomed Laser Surg. 2009 Dec;27(6):969-71. doi: 10.1089/pho.2009.2547
OBJECTIVE: Juvenile skin has been the subject of intense research efforts since ancient times. This article reports on synergistic complementarities in the biological actions of green tea and red light, which inspired the design of a green tea-assisted facial rejuvenation program.
BACKGROUND: The approach is based on previous laboratory experiments providing insight into a mechanism by which visible light interacts with cells and their microenvironment.
METHODS: After 2 months of extreme oxidative stress, green tea-filled cotton pads were placed once per day for 20 minutes onto the skin before treatment with an array of light-emitting diodes (central wavelength 670 nm, dermal dose 4 J/cm2).
RESULTS: Rejuvenated skin, reduced wrinkle levels, and juvenile complexion, previously realized in 10 months of light treatment alone were realized in 1 month.
CONCLUSION: The accelerated skin rejuvenation based on the interplay of the physicochemical and biological effects of light with the reactive oxygen species scavenging capacity of green tea extends the action spectrum of phototherapy. The duo opens the gate to a multitude of possible biomedical light applications and cosmetic formulas, including reversal of topical deterioration related to excess reactive oxygen species, such as graying of hair.
LED photoprevention: reduced MED response following multiple LED exposures
SOURCE: Lasers Surg Med. 2008 Feb;40(2):106-12. doi: 10.1002/lsm.20615
BACKGROUND: As photoprotection with traditional sunscreen presents some limitations, the use of non-traditional treatments to increase skin resistance to ultraviolet (UV) induced damage would prove particularly appealing.
OBJECTIVE: The purpose of this pilot study was to test the potential of non-thermal pulsed light-emitting diode (LED) treatments (660 nm) prior to UV exposure in the induction of a state of cellular resistance against UV-induced erythema.
METHODS: Thirteen healthy subjects and two patients with polymorphous light eruption (PLE) were exposed to 5, 6, or 10 LED treatments (660 nm) on an experimental anterior thigh region. Individual baseline minimal erythema doses (MED) were then determined. UV radiation was thereafter performed on the LED experimental and contrl anterior thigh areas. Finally, 24 hours post-UV irradiation, LED pre-treated MED responses were compared to the non-treated sites.
RESULTS: Reduction of erythema was considered significant when erythema was reduced by >50% on the LED-treated side as opposed to the control side. A significant LED treatment reduction in UV-B induced erythema reaction was observed in at least one occasion in 85% of subjects, including patients suffering from PLE. Moreover, there was evidence of a dose-related pattern in results. Finally, a sun protection factor SPF-15-like effect and a reduction in post-inflammatory hyperpigmentation were observed on the LED pre-treated side.
CONCLUSION: Results suggest that LED based therapy prior to UV exposure provided significant protection against UV-B induced erythema. The induction of cellular resistance to UV insults may possibly be explained by the induction of a state a natural resistance to the skin via specific cell signaling pathways and without the drawbacks and limitations of traditional sunscreens. These results represent an encouraging step towards expanding the potential applications of LED therapy and could be useful in the treatment of patients with anomalous reactions to sunlight.
Summary: There is strong clinical evidence that shows red light therapy can improve the health of your skin
We’ve pointed out 6 different clinical studies that demonstrate the anti-aging benefits of red light therapy. This is certainly not an exhaustive list. If you’re anxious to learn more, feel free to search PubMed.
But remember, when it comes to red light therapy, wavelength and intensity are incredibly important. Make sure you choose a device that delivers red light with the correct wavelength and an optimal amount of power.