The Bright Side of Skincare: How LEDs Influence Microbial Balance

With LED face masks and light-based skincare rapidly increasing in popularity, light has become a new frontier in skin health. Previously seen as a threat and something that we needed to block or avoid, light is now being seen as therapeutic tool. Yet beyond the visible changes to tone and texture, light also interacts with the skin microbiome. Understanding how different wavelengths influence this ecosystem is key to ensuring that light enhances, rather than harms, our skin’s microbial balance.

What we know:

• Each wavelength of light interacts differently with both skin cells and the microbes that live on them. Of the wavelengths, red and blue have been found to have the best therapeutic benefits.

• Blue light (400–470 nm) has been shown to target bacteria like Cutibacterium acnes and Staphylococcus aureus, species commonly linked to acne and inflammation. By interacting with microbial chromophores, it produces reactive oxygen species that damage bacterial membranes. This can help rebalance the microbiome when used at the right dose (Plattfaut et al., 2021).

• Red light (620–750 nm), has been shown to have anti-inflammatory and tissue-repair properties. It’s widely used in photobiomodulation therapy and research suggests that red light can enhance wound healing and reduce bacterial load when paired with blue light (Lee et al, 2007).

• Together, these wavelengths demonstrate that light can influence microbial composition and function, not just skin appearance. But precision matters: the wrong dose or wavelength could just as easily disrupt the skin microbiome.

Industry Impact and Potential

As light-based therapies and tools move from specialist clinic to home use, understanding their microbiome impact becomes essential. The skin microbiome is now a critical factor in dermatological science and, consumer skincare innovation must consider the impact in respect to the microbiome.

• Emerging research hints at the potential of personalised phototherapy tuned to an individual’s microbiome composition.

• Microbiome-safe LED protocols that support healthy microbial diversity.

• Combinations of blue and red light that offer both microbial control and skin repair.

These developments can help us redefine how we think about light, as a precision tool for microbial balance.

Our solution:

Sequential is at the forefront of microbiome product testing and development, providing tailored solutions to understand how environmental factors, such as light, influence the skin microbiome. Using advanced research techniques and supported with a database of over 50,000 human samples, Sequential offers comprehensive services to evaluate product impacts and formulations on the skin microbiome. 

Our goal is to provide science-driven insights that help brands design light-based treatments and formulations that work with the microbiome, not against it.

References:

Lee, S., You, C., & Park, M., 2007. Blue and red light combination LED phototherapy for acne vulgaris in patients with skin phototype IV. Lasers in Surgery and Medicine, 39. https://doi.org/10.1002/LSM.20412.

Plattfaut, I., Demir, E., Fuchs, P., Schiefer, J., Stürmer, E., Brüning, A., & Opländer, C., 2021. Characterization of Blue Light Treatment for Infected Wounds: Antibacterial Efficacy of 420, 455, and 480 nm Light-Emitting Diode Arrays Against Common Skin Pathogens Versus Blue Light-

Induced Skin Cell Toxicity. Photobiomodulation, photomedicine, and laser surgery, 39 5, pp. 339-348.