Scientists have proven: living organisms glow until they die

Imagine this: all living things emit light. No, not like fireflies - much weaker, this light cannot be seen with the naked eye. But it's there. And as soon as the life leaves the body, that glow disappears. Does that sound like magic? Well, it's not - it's a scientific fact, confirmed by a fresh study by scientists at the University of Calgary.

Read more: V. Salari et al, Imaging Ultraweak Photon Emission from Living and Dead Mice and from Plants under Stress, The Journal of Physical Chemistry Letters (2025). DOI: 10.1021/acs.jpclett.4c03546

They discovered that absolutely all living organisms - from plants to mice - emit tiny portions of light. This phenomenon is called ultra-weak photon emission (UPE) and, unlike bioluminescence, is not visible to the eye and does not require an external energy source. The light that occurs inside the body is a side effect of our cells.

🔬 How does it work?

Our body is a kind of chemical laboratory. There are millions of reactions going on inside all the time. Cellular metabolism produces reactive oxygen species (ROS), which help cells fight stress. When these molecules become too abundant - for example, in disease, injury or overheating - oxidative stress kicks in and the cells start processes that lead to the emission of light.

The scientists tested this on mice and plants. They placed living and dead mice in specially darkened boxes and filmed them with high-sensitivity cameras. The result was striking: the living mice literally glowed (within the spectrum of 200-1000 nm), while the radiation in the dead mice was almost zero.

In plants, on the contrary, UPE varied depending on conditions. When the temperature increased or when damaged, the leaves began to "glow" more strongly. The areas that were subjected to chemical treatments were particularly bright.

🌱 Light as a diagnostic tool

This discovery could be a real breakthrough for medicine and biology. The ability to track the state of an organism by the intensity of its "internal glow" is a fantastically accurate and non-invasive way of diagnosis. Imagine a scanner that can tell how well a plant is surviving a drought, or how well tissue recovery is going after surgery.

The research shows: UPE can serve as a biomarker of stress and viability. This is no longer just a theoretical idea, but a fact confirmed by experiments.

So, yes, there really is a glow of life inside us. And this light, even though we can't see it, can tell us much more about our health than we previously thought.