Yoga Nidra and NSDR for Cortisol: What a Rigorous 2025 Trial Actually Found

Yoga nidra, sometimes called "yogic sleep," is a guided meditation practice with roots in yogic tradition: lying down, slowing the breath, and moving through stages of body awareness while staying just conscious enough to follow the instructions. In the past few years it has been repackaged for a wellness audience under the label "non-sleep deep rest," or NSDR, a term popularized by Stanford neuroscientist Andrew Huberman. The pitch online is simple: a short daily session as a fast, low-effort way to bring down cortisol and reset an overstressed nervous system.

The strongest recent evidence comes from a 2025 randomized controlled trial published in the journal Stress and Health, led by researcher Esther Moszeik at the University of the Bundeswehr Munich. The study recruited 362 adults and randomly assigned them to an 11-minute yoga nidra practice, a 30-minute version, an active control group that listened to calming instrumental music, or a waitlist control group, with the interventions done online and ideally practiced daily over two months. A subset of 229 participants also provided saliva samples at five specific times across two consecutive days, allowing researchers to map each person's actual diurnal cortisol curve rather than relying on a single measurement.

On the psychological side, both yoga nidra durations produced statistically significant reductions in stress, anxiety, depression, and rumination compared with the waitlist group, along with a modest increase in life satisfaction. It is worth being precise about the size of these effects: researchers described them as small, in the range of roughly 8 to 16 percent of a standard deviation, though they noted that even small effects can be meaningful for a practice this low-cost and accessible. Compared against the music control specifically, the 11-minute practice showed a distinct edge only on depression symptoms, not across every measure.

The cortisol findings are more interesting, and more complicated, than a simple "it lowers cortisol" summary would suggest. The 30-minute version produced a flatter cortisol awakening response, meaning a less pronounced morning spike, compared with the control groups. Among people doing the shorter 11-minute practice, more frequent use over the two months was associated with lower total daily cortisol output and a steeper decline in cortisol from morning to evening, a pattern generally considered healthier. But among people doing the 30-minute version, more frequent practice was associated with the opposite pattern, a higher cortisol awakening response, which the researchers speculated might mean the longer practice shifts from relaxing to more activating with heavy repetition. That is a considerably messier picture than marketing built around a single "reset your cortisol" claim.

This is a useful case for separating what is proven from what is being sold. What the trial actually supports is that a free, low-risk relaxation practice produced modest, measurable improvements in self-reported stress and some shifts in cortisol patterning in a large, well-controlled sample, genuinely more rigorous evidence than most stress-and-cortisol supplement research covered on this site. What it does not support is the version of the claim aimed at skin: the study did not measure acne, redness, or any dermatological outcome, so any link between NSDR and calmer skin is inferred, not demonstrated. It also does not support a blanket "cortisol crash" promise, since the effect direction depended on session length and how often someone practiced.

For most healthy adults, yoga nidra or NSDR is a reasonable, essentially risk-free thing to try for stress and sleep, and the current evidence behind it is better than the evidence behind most trending cortisol interventions. It is just not the dramatic, one-size-fits-all cortisol fix that shorter social media summaries of the research tend to imply.