Deep Sleep Stress Response Recovery Delta Sleep–Inducing Peptide (DSIP) is a somnogenic neuropeptide studied for its ability to promote deep, slow-wave (delta) sleep — the most restorative phase of the sleep cycle when the body undergoes its most significant physical repair and neurological recovery. Research also suggests it plays a regulatory role in the hypothalamic–pituitary–adrenal (HPA) axis, helping to support balanced cortisol rhythms and a more adaptive stress response.
