Most conversations about cold therapy stay at the surface level. You feel the shock, you adapt, you feel better. But Josh Axe and Gary Brecka are doing something more useful here — they're mapping what's actually happening inside your cells when you apply controlled stress, and why some people respond dramatically while others plateau.
The core argument is about mitochondria as the organizing principle of health. Not just energy production, but cellular signaling. When you expose yourself to cold, you're not just triggering norepinephrine or brown fat activation — you're sending a stress signal deep into the cellular machinery that initiates mitochondrial biogenesis. More mitochondria. Better-functioning mitochondria. And with that, improved metabolic efficiency across every system in your body.
This aligns precisely with what I've been seeing across the knowledge base. The infrared sauna literature — particularly the Sunlighten and cell danger response material — describes the same phenomenon from a different angle. Cells stuck in what researchers call "cell danger response" lose the ability to process incoming signals, including hormetic stress signals. They're in defensive lockdown. You can stand in cold water for ten minutes and the cascade just doesn't initiate properly.
What Axe adds that I find genuinely valuable is the gut health vector. Parasite infections, he argues, directly impair mitochondrial function — not as a side effect, but as a primary mechanism. Parasites compete for nutrients, generate inflammatory byproducts, and disrupt the cellular environment that cold exposure is trying to optimize. This isn't fringe. It's consistent with the broader research on systemic inflammation as a suppressor of hormetic adaptation.
Peptide therapy is where this conversation becomes more contested. The evidence base is thinner, the regulatory landscape is complicated, and the clinical protocols vary wildly. Brecka and Axe are enthusiastic here in ways that outrun the peer-reviewed literature. That doesn't mean they're wrong — it means we're in early territory. The mechanistic reasoning is sound. The long-term data isn't there yet.
On the mitochondrial biogenesis side, though, there's genuine consensus. Cold exposure, heat exposure, fasting, exercise — they all converge on the same cellular machinery. The pathways are different, but the outcome is the same: more resilient, more numerous mitochondria.
Before investing in advanced protocols, get the foundation right. If you're experiencing persistent fatigue, cognitive fog, or inflammation that doesn't resolve with good sleep and nutrition, consider whether your gut is operating as a drain on your system rather than a foundation for it. A full gut health workup — including parasite screening — is not exotic. It's due diligence. Cold therapy works better when your cellular environment is clean enough to respond to it.
Axe mentions the Japanese model of medicine — the nearly 100,000 centenarians, the cadence of rest, the integration of traditional and functional approaches. What struck me is how this maps onto something the contrast therapy research keeps surfacing: longevity protocols work not because of any single intervention, but because of the absence of chronic stressors running in the background. The centenarians aren't doing extraordinary things. They've simply removed the drains — the toxins, the parasites, the processed food, the relentless sympathetic activation — that undermine everything else. Cold exposure, in that context, isn't the intervention. It's the reward for having cleaned house first.