LL-37 vs VIP (Vasoactive Intestinal Polypeptide)
Updated October 16, 2026 · Reviewed by the PeptidesDB Editorial team
A data-driven comparison of LL-37 and VIP (Vasoactive Intestinal Polypeptide) (also searched as VIP (Vasoactive Intestinal Polypeptide) vs LL-37) — effect profiles, evidence, side effects, and which suits weight loss, muscle, or healing goals.
Verdict
LL-37 centers on healing, while VIP (Vasoactive Intestinal Polypeptide) leans toward neuro. On indexed research, VIP (Vasoactive Intestinal Polypeptide) is ahead (LL-37: 35 studies, Human evidence; VIP (Vasoactive Intestinal Polypeptide): 40, Human clinical). Choose by goal — and read the primary studies. This is research information, not medical advice.
Key takeaways
- •LL-37 is strongest for healing; VIP (Vasoactive Intestinal Polypeptide) for neuro.
- •Evidence: LL-37 Human evidence (35 studies) vs VIP (Vasoactive Intestinal Polypeptide) Human clinical (40).
- •Both are research-use compounds — not FDA-approved.
Effect profiles, overlaid
At a glance
Neuropeptide | Gastrointestinal disorders
LL-37 vs VIP (Vasoactive Intestinal Polypeptide): side-by-side
| Metric | LL-37 | VIP (Vasoactive Intestinal Polypeptide) |
|---|---|---|
| Class | Immune | Neuro |
| Regulatory status | Research use only | Research use only |
| Evidence grade | Human evidence | Human clinical |
| Studies indexed | 35 | 40 |
| Research level | Well Studied | Moderate Research |
| Strongest effect | Healing & recovery | Neuro & mood |
| Healing & recovery | 5.0▲ | 2.0 |
| Muscle & body comp | 0.0 | 1.0▲ |
| Metabolic & appetite | 0.0 | 2.0▲ |
| Neuro & mood | 0.0 | 4.0▲ |
| Sleep & circadian | 0.0 | 2.0▲ |
| Inflammation & immune | 4.0▲ | 3.0 |
| Skin & aesthetics | 2.0▲ | 1.0 |
▲ marks the higher AI-assigned effect score (0–5, describing where the literature concentrates — not clinical efficacy).
Mechanism & pharmacokinetics
| Property | LL-37 | VIP (Vasoactive Intestinal Polypeptide) |
|---|---|---|
| Mechanism | Disrupts microbial membranes, modulates immune responses | VPAC receptor agonist |
Established pharmacology — curated for well-characterized compounds and AI-summarized otherwise. A blank (—) means no reliable single value is published (half-life figures for some peptides genuinely disagree across sources). Verify against primary sources such as FDA labels and ClinicalTrials.gov.
What is LL-37?
LL-37 is a human cathelicidin antimicrobial peptide that plays a crucial role in the innate immune response. It is produced by various cells, including epithelial cells and neutrophils, and exhibits a broad spectrum of biological activities, including antimicrobial, immunomodulatory, and wound healing properties. LL-37 interacts with a variety of pathogens, including bacteria, viruses, and fungi, contributing to the host's defense mechanisms.
Full LL-37 profile, mechanism & studies →What is VIP (Vasoactive Intestinal Polypeptide)?
Vasoactive Intestinal Peptide | Neuropeptide
Full VIP (Vasoactive Intestinal Polypeptide) profile, mechanism & studies →Which is better for your goal?
| Goal | Better fit | Why |
|---|---|---|
| Healing | LL-37 | 5.0/5 effect signal |
| Muscle | VIP (Vasoactive Intestinal Polypeptide) | 1.0/5 effect signal |
| Metabolic | VIP (Vasoactive Intestinal Polypeptide) | 2.0/5 effect signal |
| Neuro | VIP (Vasoactive Intestinal Polypeptide) | 4.0/5 effect signal |
| Sleep | VIP (Vasoactive Intestinal Polypeptide) | 2.0/5 effect signal |
| Inflammation | LL-37 | 4.0/5 effect signal |
| Skin | LL-37 | 2.0/5 effect signal |
Fit reflects community-perceived effect profiles — not head-to-head trials. Read each peptide's studies before deciding.
Can you stack LL-37 and VIP (Vasoactive Intestinal Polypeptide)?
People sometimes combine peptides that target different pathways, but there is little controlled research on this specific pairing and the interactions aren't well characterized. Because neither compound is FDA-approved, we don't publish stacking or dosing protocols here. Any combination should be discussed with a qualified clinician.
LL-37 vs VIP (Vasoactive Intestinal Polypeptide): side effects
No community-reported effects logged yet.
No community-reported effects logged yet.
Anonymous community reports (count = number of reports), not clinical incidence rates.
What the research says
LL-37 has 35 approved studies indexed (Human evidence), and VIP (Vasoactive Intestinal Polypeptide) has 40 (Human clinical). The Librarian re-checks PubMed, Europe PMC and ClinicalTrials daily, so these counts move. Open each profile to read the summaries and sources.
Frequently asked questions
Is LL-37 or VIP (Vasoactive Intestinal Polypeptide) better?
It depends on your goal. LL-37 is strongest for healing; VIP (Vasoactive Intestinal Polypeptide) for neuro. VIP (Vasoactive Intestinal Polypeptide) has more indexed studies (40). See the goal-by-goal breakdown above.
Is LL-37 or VIP (Vasoactive Intestinal Polypeptide) better for weight loss?
VIP (Vasoactive Intestinal Polypeptide) shows the stronger metabolic & appetite profile (2.0/5) in the AI-assigned effect profile — though weight-loss outcomes depend on the individual and the evidence base.
Is LL-37 or VIP (Vasoactive Intestinal Polypeptide) better for muscle?
VIP (Vasoactive Intestinal Polypeptide) leads on the muscle & body-composition axis (1.0/5).
Which has more research, LL-37 or VIP (Vasoactive Intestinal Polypeptide)?
LL-37 has 35 approved studies indexed (Human evidence); VIP (Vasoactive Intestinal Polypeptide) has 40 (Human clinical). Higher counts mean more to read, not proven superiority.
Can you stack LL-37 and VIP (Vasoactive Intestinal Polypeptide)?
Some users combine peptides, but there's little controlled data on this specific pairing, and interactions aren't well characterized. We don't publish stacking protocols for compounds that aren't FDA-approved. Discuss any combination with a qualified clinician.
What are the side effects of LL-37 vs VIP (Vasoactive Intestinal Polypeptide)?
LL-37: no community-reported effects logged yet. VIP (Vasoactive Intestinal Polypeptide): none logged yet. These are anonymous reports, not incidence rates — see each profile.
Is LL-37 or VIP (Vasoactive Intestinal Polypeptide) FDA-approved?
LL-37 is a research-use compound and is not FDA-approved. VIP (Vasoactive Intestinal Polypeptide) is not FDA-approved. Research-use status is not a legal clearance to compound or use in humans.
Is VIP (Vasoactive Intestinal Polypeptide) better than LL-37?
For neuro, VIP (Vasoactive Intestinal Polypeptide) has the edge; for healing, LL-37 does. Neither is universally "better" — it's goal-dependent, and both should be weighed against their evidence base above.
Comparing related peptides
Regulatory & legal status
LL-37 and VIP (Vasoactive Intestinal Polypeptide) are research-use compounds and are not FDA-approved for human use. FDA approval and compounding rules for peptides change frequently, and research-use status is not a legal clearance for human use. The FDA does not review compounded drugs for safety, effectiveness, or quality. Verify current status with primary sources before acting. Last reviewed October 16, 2026.