Photons, mitochondria
and infrared light

We usually picture biology as chemistry — molecules bumping into each other. But at the deepest level, life is governed by physics. One of the most fascinating fields is quantum biology: the study of how individual photons and electrons affect living cells. Light therapy is a practical example of it.

A photon is the smallest possible dose of light — a quantum. When such a photon of the right wavelength lands on the right molecule in a cell, it can trigger a chain of events that ends in the production of energy. It doesn't heat the cell or destroy it — it simply hands it a precisely measured piece of energy and information.

Why red and infrared light

Not all light penetrates the body equally. Short wavelengths (blue, ultraviolet) are absorbed at the very surface of the skin. Red and near-infrared light (roughly 630–1100 nm), by contrast, passes through the so-called "optical window" of tissue — a band in which neither blood nor water absorbs it strongly, so it reaches deeper.

As a result, red light acts on the skin and surface tissues, while infrared wavelengths reach muscles, joints, tendons and deeper structures. That is why a therapy panel combines several wavelengths at once — each "serves" a different depth.

Mitochondria: the cell's power plants

Almost every cell contains dozens to thousands of mitochondria — tiny organelles that produce ATP, the cell's universal fuel. They do this using a chain of proteins through which a current of electrons "flows". The last link of this chain is the enzyme cytochrome c oxidase.

And this enzyme is key: it can absorb photons of red and infrared light. When they land on it, research suggests that nitric oxide — which had been braking its activity — is released, the chain runs more efficiently, and the cell makes more ATP. In short: light helps mitochondria work better.

Water that isn't quite liquid

Newer, still-studied hypotheses go further. They suggest that infrared light may also affect the structure of water around cell membranes — so-called "structured" water — and thereby ease the flow of energy in the cell. This area is still under research, and it is wise to approach it with caution; it is not a settled matter, but a direction actively being studied.

Hormesis: why less is often more

An important principle of light therapy is hormesis: a mild, controlled stimulus brings benefit, but too much of the same stimulus loses the effect. In photobiomodulation this means a reasonable dose of light helps, while "more is better" does not hold. That is why therapy protocols have recommended times and intensities — and why it is useful to be able to control the dose precisely.

A panel with several wavelengths and independent channels enables exactly that: delivering the right combination of photons to the right depth, in a reasonable dose. Not more light — the right light.