Does red light therapy really have an effect on your cells?
Based on the available sources, we cannot answer this question fairly: there is not a single study on red light therapy included. For a well-informed answer, consult studies that have specifically investigated photobiomodulation in humans.
The available research sources do not contain a single study on red light therapy or photobiomodulation. As a result, it is not possible to make a well-founded statement about its effects on cells based on these sources.
That does not mean there is no research into this topic anywhere in the world, but it does mean that we cannot give you a fair, evidence-based answer at this time without going beyond our sources.
If you want to know what red light therapy does at the cellular level, look specifically for research using the term 'photobiomodulation', and pay attention to whether the results come from animal or laboratory studies, or whether studies in humans have also been conducted. That distinction makes a big difference for what you can realistically expect from it in practice.