Mitochondria are the powerhouses of our cells and play a crucial role in the body's energy production. Without properly functioning mitochondria, our cells would have no energy to survive. An important factor in this process is ATP (adenosine triphosphate), the primary energy carrier in our bodies. Recent research suggests that red light therapy (photobiomodulation) may have a beneficial effect on mitochondrial function and ATP production. But how exactly does it work?

In this comprehensive explanation, we will cover:

1. How mitochondria produce ATP
2. Why ATP is so important for the body
3. How red and near-infrared light affect mitochondria
4. The scientific basis behind light therapy and mitochondrial stimulation

What is ATP and why is it important?

ATP (adenosine triphosphate) is a molecule considered the universal energy currency of the body. Nearly all biological processes, such as muscle contraction, nerve signaling, enzyme activity, and cell growth, require energy, and that energy is supplied by ATP.

When a cell needs energy, it breaks down ATP into ADP (adenosine diphosphate) and a phosphate molecule, releasing energy that the cell can use directly. Mitochondria recycle ADP back into ATP by storing energy from nutrients. This process, known as oxidative phosphorylation, is essential for the survival and function of cells.

How mitochondria produce ATP: A step-by-step explanation

1. Glycolysis (the first step in ATP production)

Energy production begins in the cell's cytoplasm, where glucose is broken down into pyruvate. This process is called glycolysis and produces a small amount of ATP.

• Important point: Glycolysis can take place without oxygen, but produces much less ATP than mitochondrial processes.

2. The citric acid cycle (Krebs cycle)

The pyruvate produced by glycolysis is then transported to the mitochondria, where it is converted into acetyl-CoA. This molecule enters the citric acid cycle (also known as the Krebs cycle).

• During this cycle, electrons and protons are extracted and transferred to the electron transport chain.
• This process generates energy-rich molecules such as NADH and FADH₂, which are needed for the next step.

3. The electron transport chain: Where ATP is really made

The electron transport chain (ETC) is located in the inner membrane of the mitochondria and is the most efficient way cells produce ATP.

• Electrons from NADH and FADH₂ are transported through a series of proteins in the ETC.
• This transport leads to the pumping of protons (H⁺) into the intermembrane space of the mitochondrion, creating an electrochemical potential difference.
• Ultimately, these protons are used by the enzyme ATP synthase to convert ADP back into ATP.

4. The importance of oxygen

Oxygen is essential in this process because it serves as the final electron acceptor in the chain. This prevents the accumulation of electrons and maintains the flow of electrons and protons. Without oxygen, oxidative phosphorylation stops, and the cell must fall back on less efficient energy production, such as fermentation.

How does light penetrate tissue and affect the mitochondria?

Light, especially in the red and near-infrared spectrum, can penetrate deeply into biological tissues. This ability is influenced by the wavelength of the light:

• Red light (600-700 nm): Penetrates a few millimeters into the skin and mainly affects superficial tissues such as the skin, hair follicles, and superficial blood vessels.
• Near-infrared light (700-1100 nm): Has deeper penetration and can reach muscles, joints, and even brain tissue.

How light stimulates the mitochondria

The core mechanism by which light therapy stimulates mitochondria is through interaction with cytochrome c oxidase (CCO), an important enzyme in the electron transport chain.

• Cytochrome c oxidase absorbs photons from red and near-infrared light and uses this energy to improve oxygen-binding efficiency.
• This can support ATP production and improve the energy supply to cells.

Additionally, this stimulation leads to:

• Reduced oxidative stress because the cell can neutralize reactive oxygen species (ROS) more effectively.
• Increased blood circulation, allowing cells to receive oxygen and nutrients more quickly.
• Less inflammation, because ATP is essential for recovery processes.

Commonly used wavelengths in red light therapy

Not all wavelengths work the same way. The most studied wavelengths for mitochondrial stimulation are in the red (600-700 nm) and near-infrared (700-1100 nm) spectrum.

Here are the most studied wavelengths and their effects:

630 nm (Red light)

• Stimulates the production of collagen, which benefits the skin.
• Supports skin recovery and helps reduce inflammatory responses.
• Suitable for superficial skincare and tissue repair.

Scientific research:

• A study by Palwankar et al. (2024) described photobiomodulation with red light wavelengths as supporting tissue repair and reducing inflammatory responses in dental applications. Read more

660 nm (Deep red light)

• Penetrates deeper than 630 nm and stimulates mitochondrial ATP production.
• Helps with muscle recovery and reduces muscle fatigue.
• Promotes reduced inflammation and tissue repair.

Scientific research:

• An article in Frontiers in Cell and Developmental Biology (2024) describes that 660 nm light increased mitochondrial activity and reduced oxidative stress. Read more

810 nm (Near-infrared light)

• Passes through the skull and supports brain health.
• Being studied in relation to brain function during aging.
• Associated with blood circulation in the brain.

Scientific research:

• Zhang et al. (2024) investigated the effect of 810 nm light on brain function and mitochondria, and described a supportive effect on brain cells. Read more

850 nm (Near-infrared light)

• Penetrates deeply into tissues and muscles.
• Being studied for support with joint pain and stiff joints.
• Stimulates muscle recovery and tissue regeneration.

Scientific research:

• A study in ScienceDirect (2024) found that 850 nm light reduced oxidative stress and activated mitochondria in muscle cells. Read more

940 nm (Near-infrared)

• Penetrates very deeply into the body and affects internal organs.
• Improves blood circulation and oxygen transport.
• Supports lymphatic drainage and detoxification.

Scientific research:

• A study by Vieira et al. (2024) described that 940 nm light can activate mitochondria in the cardiovascular system. Read more

1060 nm (Deepest penetration)

• Has the deepest penetration and may influence the energy metabolism of deeper tissue.
• Being investigated in relation to cellular metabolism and vitality.
• Being investigated for applications in deeper tissue.

Scientific research:

• A recent publication in IEEE Transactions (2025) describes the effects of 1060 nm light on metabolic functions in deeper tissue. Read more

Summary and conclusion

Mitochondria play a fundamental role in our body's energy production. They convert nutrients into ATP, the molecule that supplies energy for all biological processes. ATP is generated through glycolysis, the citric acid cycle, and the electron transport chain in mitochondria.

Red light therapy stimulates mitochondria by activating the enzyme cytochrome c oxidase, which may support ATP production. Specific wavelengths, such as 630 nm, 660 nm, 810 nm, 850 nm, and 940 nm, penetrate to different depths in the body and support energy production, muscle recovery, brain function, and inflammation reduction.

Light can therefore support energy production in our cells, which may contribute to performance, recovery, and potentially support brain function.

Want to optimize mitochondrial function and ATP production? Red light therapy may be a natural way to support your cellular energy and vitality. Results vary from person to person.

Red light therapy is a wellness application and not a substitute for medical care. Results vary from person to person; consult your doctor if you have symptoms.