It's not just "anxiety" but a nervous system stuck on alert — cortisol supposedly tightens the chest and shortens the breath; regulating the nervous system (not just "calming down") would quickly undo that.

noli's read

The central idea — that shallow breathing and chest tightness come from autonomic nervous system activation rather than a willpower failure — is well established physiologically, but the immediate mechanism at play is mostly adrenaline/noradrenaline (a fast sympathetic response), not cortisol, which acts on a scale of minutes to hours rather than second to second; this is a common mix-up in wellness content. That said, the claim that "regulating the nervous system" works better than "forcing yourself to calm down" is solidly supported: our own science base documents that the physiological sigh (two nasal inhales, one long exhale) improves mood and slows breathing more effectively than meditation in a controlled trial (Balban et al., 2023), and that slow breathing produces a real, measurable parasympathetic shift within minutes. The specific paid method being sold ("The Shift") isn't evaluated here. Verdict: mixed — the symptom and the general solution (regulate rather than force) are well supported, the specific attribution to "cortisol" is an approximation.

the sources

1. 1Balban MY, Neri E, Kogon MM, et al. 2023
2. 2Fincham GW, Strauss C, Montero-Marin J, Cavanagh K. 2023
3. 3Zaccaro A et al. 2018