Research
Hormonal
AgRP neurons promote feeding and inhibit energy expenditure by antagonizing MC4R, and their activity is increased during fasting/starvation.
During fasting, your body activates AgRP neurons to drive hunger and conserve energy. This is a normal survival mechanism. Understanding this helps explain why hunger increases when you restrict calories.
StrongSupportsVERY_HIGH confidence
Conversely, in the ‘starved state’ activity of agouti-related neuropeptide (AgRP) and of neuropeptide Y (NPY)-expressing neurons is increased by decreased levels of circulating leptin and insulin and by the orexigenic hormone ghrelin to promote food intake.
Why this rating
Supported by extensive genetic and pharmacological evidence cited in the review.
Source
The melanocortin pathway and control of appetite-progress and therapeutic implications
Giulia Baldini et al. · Journal of Endocrinology · 2019
DOI 10.1530/joe-18-0596
narrative_reviewCited 271×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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