Fibroblast Growth Factor 21
Also known as: FGF-21, fgf21, fgf 21, fibroblast growth factor-21
Fibroblast growth factor 21, or FGF21, is a hormone like member of the fibroblast growth factor family, produced mainly in the liver. The mature human form spans 181 amino acids, and it is studied in metabolic research for its effects on glucose handling and insulin sensitivity.
Quick Reference
Fibroblast Growth Factor 21 - Research Images
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Mechanism of Action
FGF21 requires the co-receptor KLB to signal. In differentiated fat cells it increases expression of the glucose transporter GLUT1, which raises glucose uptake, while having little effect on GLUT4 expression. Through this pathway it is studied for its role in whole body glucose balance and insulin sensitivity.
Research History
FGF21 was recognized as an atypical fibroblast growth factor that acts more like a circulating hormone than a local growth signal. Research attention grew around its metabolic effects in fat tissue, including its ability to raise glucose uptake in adipocytes, and it is now a central molecule in studies of metabolic stress signaling alongside GDF15.
What Researchers Are Saying
Community Reports - Not Medical Advice
The following is aggregated from public forums, Reddit, and research communities. These are anecdotal reports from researchers only - not verified clinical data and not a recommendation of any kind.
Fibroblast Growth Factor 21 (also known as FGF-21, fgf21) is studied within the longevity and anti-aging research community. Hepatokine studied for metabolic regulation, longevity signaling, and improved insulin sensitivity.
Last updated October 28, 2026
Research status: active. Fibroblast Growth Factor 21 appears across longevity and anti-aging research forums and academic literature. Researchers note this compound falls in the anti aging category.
Last updated October 28, 2026
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