DSIP stands for delta sleep-inducing peptide, a nine amino acid chain isolated in 1977 from rabbits that had been put into a sleep-like state. It was named for what researchers hoped it did: promote delta waves, the slow brain rhythm of deep sleep.
Nearly fifty years later, the name still promises more than the evidence delivers.
It is found mainly in the hypothalamus, the part of the brain that governs sleep and hormone rhythms, and levels in the blood follow a daily cycle. That much is established. What it actually does there has never been pinned down, and it does not fit neatly into any known receptor system, which is unusual for a peptide with this much history.
It circulates online as a sleep aid, and it is one of the few peptides in that space with any human trial data at all. The trouble is that the trials are small, old, and inconsistent.
For educational and research purposes only. Never use any peptide or substance based on information found here — always consult a licensed healthcare professional before making any medical or health-related decision.
No reviews yet. Be the first.
DSIP is a case where fifty years of research has produced remarkably little certainty.
The encouraging result came from a small study of six healthy volunteers given intravenous DSIP, where total sleep time rose by 59 percent in the window after treatment compared with placebo. Delayed effects on the following night included faster sleep onset and better sleep efficiency.
The results in people with actual insomnia were far weaker. A double blind study in chronic insomniacs found higher sleep efficiency and shorter sleep latency, but the authors noted the effects were weak, possibly explained in part by a chance shift in the placebo group, and concluded that short term DSIP treatment was unlikely to be of major therapeutic benefit. That is a discouraging conclusion coming from the researchers themselves.
There is also a confusing wrinkle in the basic biology. Some work suggests that natural rises in circulating DSIP are associated with suppressed slow wave and REM sleep, which is the opposite of what the name implies.
More recent work has been in animals, including fusion peptide designs aimed at getting it across the blood brain barrier more reliably. That research direction is itself a hint that delivery of the plain peptide may be a limiting factor.