Red LED light therapy is a powerful tool in many beauty therapists’ treatment arsenals. But how does it actually work? We take a deep dive into the science behind the treatment.
What is red light therapy?
Red light therapy is one of the most popular beauty treatments out there for several reasons. It can be used as a standalone treatment or easily added to other therapies. It's low effort for practitioners, non-invasive, requires no downtime and clients often see remarkable results.
The red light used in beauty devices comprises two parts of the electromagnetic spectrum: visible red light and near-infrared light (also called infrared-A). Visible light is the part of the spectrum that the human eye can see.
However, while it appears as a single colour, it’s actually made up of a range of colours – something visible when light travels through a prism. Near-infrared light lies just beyond the visible spectrum.
“There are two types of red light, namely warm and cold red light,” says Dr Alexander Wunsch, scientific consultant for JK Group. “In the context of beauty applications, cold red light is used. Cold red light is easiest to produce with LEDs and laser light sources.”
Red light therapy involves using LED devices to expose the skin to low levels of both red visible light and near-infrared light to stimulate cellular activity.
“Visible red light, with a wavelength ranging from 600 nanometres to 700 nanometres, reaches approximately 8-10mm into skin tissue. This makes red light particularly helpful for addressing skin issues affecting the upper dermis and epidermal layers,” explains Ellie Clark, global account development and training specialist at Déesse Pro.
Benefits of red light therapy
Red light therapy offers a diverse range of benefits for the skin, depending on the application. These benefits include improving wound healing, enhancing blood circulation, reducing inflammation, addressing blemishes and acne and combatting signs of ageing.
“A well-studied effect of red light is the stimulation of fibroblasts, which are responsible for the production of the collagen network and elastin synthesis in the skin,” comments Dr Wunsch. “As red light and near-infrared have a high penetration depth, they can support and improve numerous cell-mediated skin functions gently yet effectively.”
Dr Wunsch adds, “The effects on the mitochondria and the production of adenosine triphosphate (ATP) have been best investigated. Mitochondria also play a role in the production of hormones and antioxidants, leading to corresponding effects.
“For instance, several ageing effects are attributed to mitochondrial dysfunction, which explains the positive impacts of red light on tissue regeneration and skin rejuvenation.”
Extensive research supports the effectiveness of red light therapy. “If you search the most important scientific databases for the keywords ‘photobiomodulation’ and ‘low-level light therapy (LLLT)’ – the scientific terms for cold red light and near-infrared – you’ll find around 100,000 hits. Studies have been published on this topic since the 1960s,” says Dr Wunsch.
Best practices for using red light therapy
The application of red light should align with the specific skin issue being treated. Dr Wunsch notes that there are effective windows for optimal results; not all wavelengths and irradiance levels lead to the desired outcomes.
“In particular, the idea that higher intensity always improves the effect is a misconception,” he explains. He recommends purchasing equipment from a recognised manufacturer to ensure compliance with applicable standards and quality guarantees.
The frequency of treatments can vary. Dr Wunsch comments, “In a study I supervised, two to three applications per week were conducted, with each session lasting 15 to 20 minutes. Since cold red light is generally well tolerated, you can continue with one to two applications per week after an initial intensive phase.”
Following the manufacturer’s instructions is crucial, as they will have the necessary information on application parameters from which the dose and frequency can be derived. A trial session of three to five minutes is generally recommended for all light applications.
If no undesirable effects occur within 24 hours of application, the actual series of treatments can begin according to the manufacturer’s guidelines.
Generally, skin that is more imbalanced will see more significant benefits from red light therapy than healthier skin.
Short-term issues, such as wound healing and inflammation reduction, yield faster results than chronic concerns, which usually require long-term application.
To maximise results, it’s essential to prep the skin before treatments. Clark explains, “Before red light therapy sessions, we recommend cleansing the skin thoroughly to remove any makeup, dirt or skincare products. Clean skin ensures better light penetration and maximises the effectiveness of LED light therapy.”
Enhancing treatments with combination therapies
While red light therapy is a powerful treatment on its own, it also complements other beauty treatments, making it an excellent add-on or finishing touch.
Clark notes, “Light therapy treatments can be seamlessly integrated with additional treatment protocols and all skincare ingredients to achieve optimal results.”
Along with blue light therapy, it is often used alongside regular facials to increase the absorption and penetration of active ingredients. It also pairs well with more intense treatments like microneedling and peels, as it helps reduce inflammation.
The popularity of red light therapy is partially due to its near-universal tolerance. “Notably, LED therapy boasts an impeccable safety record with no serious adverse incidents recorded across over 1,700 publications,” says Clark.
However, this doesn’t mean it’s safe for all clients, and a thorough consultation is essential.
“There is a group of autoimmune diseases referred to as ‘collagenoses’ where red light therapy has a negative effect and would be contraindicated,” explains Dr. Wunsch.
“In general, it’s advisable to consult with the attending physician for all manifest diseases. And – this cannot be emphasised enough – the right dose is the best guarantee for an optimum effect. Always follow the manufacturer's instructions to avoid overdosing.”
This article has been adapted from the original article published in the June 2024 issue of Professional Beauty magazine.
