Hi Reader
You may have seen the headlines this week about a "unifying theory of fatigue" — a new study suggesting that ME/CFS, long Covid, PTSD, rheumatoid arthritis and multiple sclerosis might share common biological roots.
As someone who works with fatigued patients every single week, I want to give you the honest version of this story — because the real finding is more useful than the headline.
What they actually found
Researchers compared genomic data across all five conditions and found that, while the individual genes involved were mostly different, the broader systems those genes plug into kept overlapping: immune signalling, mitochondrial energy production, stress-hormone regulation, and neurotransmitter balance.
In other words — five very different illnesses appear to be leaning on some of the same physiological machinery, even without a shared genetic cause.
What it doesn't mean
It doesn't mean these are secretly the same disease. It doesn't mean one test could now diagnose all five. And it doesn't mean a treatment that helps one condition will automatically help another. The study is early-stage, computational, and funded by the company whose technology it's built on — so independent replication matters before any of this changes clinical practice.
Why I'm sharing it anyway
Because it puts real scientific weight behind something I say constantly in clinic: fatigue is almost never one thing.
This is the whole premise behind how I think about MitoImmune — the idea that your mitochondrial (energy), immune, nervous system, and adrenal/stress physiology are never working in isolation. They're in constant conversation. Two people can present with identical exhaustion, and yet the weighting of what's actually driving it — immune activation, HPA-axis dysregulation, thyroid status, nutrient depletion, sleep disruption, unresolved stress, or cellular energy metabolism — can be completely different from one person to the next.
It's also why you can have "normal" bloods and still feel far from well. Normal on a standard panel often just means we haven't looked at the right layer yet.
The takeaway
Shared systems don't mean shared root causes. If your fatigue has never quite fit a single label, that's not a gap in the science failing you — it may be exactly what this kind of research is starting to explain.
If you want to understand what's actually driving your fatigue rather than which label it might fall under, hit reply or book a functional assessment — I'd love to help you get underneath it.
In Goode Health
Nicole