Insulin vs LL-37

A side-by-side comparison from PeptideSciences101, the open peptide reference.

Overview

Insulin is primarily a weight management & metabolic peptide, while LL-37 is used for immune support.

This page compares Insulin and LL-37 across their primary use, typical dosing, reported benefits and side effects, and U.S. regulatory status. For the full monograph on either compound — mechanism of action, clinical research, and references — follow the article links.

Side-by-side comparison

InsulinLL-37
CategoryWeight Management & MetabolicImmune Support
Regulatory status (US)FDA approvedCompounding (Rx) — Apr 2026
Typical dosageHighly individualized; type 1 diabetes basal-bolus regimens typically require 0.5–1.0 units/kg/day total; type 2 diabetes is often initiated with basal insulin at 10 units or 0.1–0.2 units/kg/day, titrated to individual glycemic targets2-5 mg
FrequencyOnce daily (long-acting basal analogs) to four or more times daily (basal-bolus or continuous subcutaneous insulin infusion); prandial doses given 0–15 minutes before meals for rapid-acting analogs or 30 minutes before meals for regular human insulintwice weekly
Reported benefitsGlycemic control, prevention of diabetic ketoacidosis, reduction of microvascular complications (retinopathy, nephropathy, neuropathy), life-sustaining therapy in type 1 diabetes, HbA1c reduction in type 2 diabetesAntimicrobial activity, immune modulation, wound healing, anti-inflammatory
Reported side effectsHypoglycemia, weight gain, injection-site lipohypertrophy, rare hypersensitivity reactions, peripheral edema at initiationGenerally safe, minimal side effects

Key differences

Primary use. Insulin is categorised under Weight Management & Metabolic, while LL-37 falls under Immune Support. Their differing categories mean they are usually chosen for different goals rather than as direct substitutes.

Regulatory status. Insulin: FDA-approved. LL-37: not FDA-approved; compounding permitted with a prescription as of April 2026.

Dosing. Insulin is typically dosed at Highly individualized; type 1 diabetes basal-bolus regimens typically require 0.5–1.0 units/kg/day total; type 2 diabetes is often initiated with basal insulin at 10 units or 0.1–0.2 units/kg/day, titrated to individual glycemic targets (Once daily (long-acting basal analogs) to four or more times daily (basal-bolus or continuous subcutaneous insulin infusion); prandial doses given 0–15 minutes before meals for rapid-acting analogs or 30 minutes before meals for regular human insulin). LL-37 is typically dosed at 2-5 mg (twice weekly).

Can you stack them?

Some protocols combine peptides, but stacking Insulin and LL-37 has not been validated for safety or efficacy in controlled trials. Combining compounds can change their effects and risks. Nothing here is medical advice — consult a qualified healthcare provider before starting or combining any protocol.

Frequently asked questions

What is the difference between Insulin and LL-37?
Insulin is primarily a weight management & metabolic peptide, while LL-37 is used for immune support. Insulin is FDA-approved for one or more indications, whereas LL-37 is not FDA-approved; compounding permitted with a prescription (as of April 2026).
What is Insulin used for?
The foundational peptide hormone for glycemic management in type 1 and type 2 diabetes mellitus.
What is LL-37 used for?
Antimicrobial defense peptide.
Can you take Insulin and LL-37 together?
Some users combine peptides within a single protocol, but stacking Insulin and LL-37 has not been established as safe or effective in controlled trials. Neither this comparison nor PeptideSciences101 is medical advice — consult a qualified healthcare provider before combining any compounds.
Is Insulin or LL-37 FDA-approved?
Insulin is FDA-approved for one or more indications. LL-37 is not FDA-approved; compounding permitted with a prescription (as of April 2026).

Read the full articles

  • Insulin — full monograph: mechanism, research, dosing & references
  • LL-37 — full monograph: mechanism, research, dosing & references

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