Research
Hormonal
Insulin and leptin function as redundant adiposity signals to the brain, where they share downstream melanocortin signaling pathways to regulate food intake and energy expenditure.
Your body uses insulin and leptin to tell your brain how much fat you have stored. When these signals are high, your brain reduces hunger and increases energy use. When they are low (fasting/weight loss), hunger increases. This is a biological defense mechanism, not a failure of willpower.
StrongSupportsVERY_HIGH confidence
Recent studies have demonstrated that both insulin and leptin have additive effects when administered simultaneously. Finally, we recently have demonstrated that leptin and insulin share downstream neuropeptide signaling pathways.
Why this rating
The paper is a comprehensive review citing decades of consistent experimental data across multiple species.
Source
Insulin and Leptin as Adiposity Signals
S.C. Benoit · Recent Progress in Hormone Research · 2004
DOI 10.1210/rp.59.1.267
narrative_reviewCited 264×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Insulin acts as a rapid, minute-to-minute indicator of energy balance that tracks acute metabolic changes better than leptin, which reflects stable total fat mass.Strong
- Obesity results from dysregulation of the hypothalamic melanocortin system, where antagonists like AgRP block the anorexic effects of insulin and leptin.Strong
Related findings · Hormonal
- Initial treatment for type 2 diabetes should be a combination of metformin and either an SGLT-2 inhibitor or a GLP-1 receptor agonist to achieve cardiorenal protection, rather than monotherapy or older agents like sulfonylureas.Strong
- For patients with specific monogenic obesity syndromes (leptin deficiency, POMC/PCSK1/LEPR mutations), targeted pharmacotherapy (recombinant leptin or setmelanotide) is highly effective and should be prioritized, unlike in polygenic obesity.Strong
- Continued weekly administration of 2.4 mg subcutaneous semaglutide prevents weight regain and promotes further weight loss in adults with overweight or obesity, whereas switching to placebo results in significant weight regain.Strong
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →