Tantra is a family of practices — paced breathing, chanting with imagery, vigorous posture sequences, guided deep relaxation, and in some lineages a slow partnered sexual practice — used for calm, sleep and wellbeing. No study has tested tantra as a whole; its parts give genuine but modest gains in anxiety, sleep and blood pressure. Harms are concrete: unsettling psychological experiences, joint injury, an unregulated teaching field. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Resting blood pressure | 110–120 / 70–78 mmHg | The one validated surrogate on which pooled trial benefit exists |
| Salivary cortisol, morning and evening pair | Morning clearly higher than evening; slope steepening from own baseline | Tracks the stress-axis change tantric practice is claimed to produce |
| Resting heart rate | 50–65 bpm | Cheap proxy for the vagal shift paced breathing produces |
| Heart rate variability | No established target; track direction against own 30-day baseline | Direct readout of the parasympathetic tone the breathing practices target |
| PSA (prostate-specific antigen) | Below 2.5 ng/mL under age 60; below 4.0 ng/mL thereafter | Only relevant marker for the ejaculation-retention trade-off |
| hs-CRP | Below 1.0 mg/L | General inflammatory load; contextualises stress-axis change |
| HbA1c | 4.8–5.4% | Guards against the assumption that practice substitutes for metabolic control |
| Sexually transmitted infection panel | Negative | Directly tracks the exposure risk of partnered and group formats |
Cadence: Blood pressure weekly for four weeks, then quarterly; sleep and anxiety questionnaires at four and twelve weeks, then six-monthly; cortisol pairs and PSA annually; infection screening before each new partner or group format.