Why Wavelengths Are Crucial

Light is not just a source of brightness, but also a form of energy that can deeply intervene in biological processes. Light is frequency – and different frequencies have different colors and wavelengths. These wavelengths are measured in nanometers (nm).

When we talk about the topic: "Which wavelength should I choose for my red light therapy?", there are some important basics to understand:

• Light has different colors and groups: UV, visible light (violet to red), and infrared.

• Only the range between 600–900 nm, known as the "therapeutic window," is suitable for red light therapy.

• In this range, light particularly affects the enzyme Cytochrome C Oxidase (CCO) in the mitochondria, which is responsible for the production of ATP (cellular energy).

Three Main Factors for Choosing the Ideal Wavelengths:

1. CCO Efficacy – How well the wavelength activates the enzyme Cytochrome C Oxidase.

ATP is the energy molecule of every cell. Mitochondria are the "powerhouses" of the cells. Certain light wavelengths stimulate the enzyme Cytochrome C Oxidase, leading to:

• Increased ATP production

• Improved cellular respiration

• Reduction of oxidative stress

• Enhanced regeneration

Effectiveness Curve of CCO Activation by Light

Research shows that light in the range of 630–670 nm and 810–850 nm significantly increases CCO activity. 830 nm stands out as a peak value.

2. Penetration Depth – How deeply light can penetrate skin, muscles, and tissue.

Light is an electromagnetic wave – depending on its wavelength (measured in nanometers, nm), it is absorbed or scattered to different extents before reaching deeper tissue layers. Therefore, crucial for light therapy is the question of how deeply which light penetrates the tissue – and what happens there.

Short-Wavelength Light (380–550 nm: Blue, Green)

• Is strongly scattered and absorbed by melanin and hemoglobin, therefore penetrates barely deeper than 0.5 mm into the skin.

• These wavelengths are well-suited for acute surface treatments, such as for acne or antibacterial effects, but not for deeper therapeutic goals.

Red Light (600–700 nm: Visible Red)

• Is moderately absorbed, penetrates about 1–3 mm deep into the tissue.

• Specifically activates cells in the epidermis and dermis, especially fibroblasts (collagen formation), keratinocytes (wound healing), as well as skin stem cells.

• Very effective for skin rejuvenation, inflammation reduction, wound healing, and pain therapy in the skin and superficial connective tissue.

Near-Infrared Light (700–900 nm: NIR-I)

• Low absorption, little scattering – therefore high tissue penetration up to 6–7 mm.

• These wavelengths reach deeper structures such as:

  • Muscle fibers

  • Tendons

  • Joints

  • Peripheral nerves

• In the mitochondria, NIR light activates Cytochrome C Oxidase (CCO), which increases ATP production, accelerates cell metabolism, and supports regeneration.

Long-Wavelength Infrared (>1000 nm)

• Is increasingly absorbed by water molecules in the tissue.

• Although theoretically deeply penetrating, this leads to increased heat generation and can damage tissue.

• For this reason, the safe and effective window of 600–900 nm is mostly used in light therapy – the so-called "therapeutic window."

✅ Summary: Which Wavelength for Which Goal?

3. Scientific Evidence – The number of high-quality studies on the respective wavelength.

The diagram above shows the number of scientific studies on different wavelengths in light therapy. The diagram clearly highlights which wavelengths have been most frequently used and documented in research – e.g., 660 nm, 810 nm, and 630 nm. This data supports the selection for Heilys panels.

Wavelength Overview of heilys Gen Panels

Most commercial panels rely on 660 + 850 nm, as these are cheap and readily available (originally developed for plant lighting). heilys, however, takes a different approach:

With limited power per panel, it is crucial to strategically combine effective and scientifically proven wavelengths:

• 630 nm – Stimulates skin cells, promotes collagen formation

• 660 nm – Classic for wound healing and pain relief

• 670 nm – Particularly effective for mitochondrial ATP production

• 810 nm – Very deep tissue, muscle regeneration, brain

• 830 nm – Highest CCO activation (according to studies)

• 850 nm – Complementary to deep action, often in muscles and joints

Application Overview of Wavelengths

🔬 Study Support: How can the efficiency of CCO activation be increased by combining individually controllable wavelengths? 

• 81.7% matching to oxidized CCO absorption curve (Tran et al., 2024)

• Combinations such as 630/660/830 show significant increases in cell activity and wound healing in studies (Leal-Junior & Tomazoni, 2019)

heilys Offers More Than Standard

Thanks to evidence-based selection, heilys panels cover both superficial and deep application areas. The combination of several scientifically validated wavelengths and their targeted use clearly distinguishes heilys from classic products – for maximum effect with limited light output.