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FGL vs Follistatin

A detailed comparison to help you understand the differences and choose the right peptide for your research goals.

FGL

FGL (FG Loop) is a synthetic peptide that mimics the neural cell adhesion molecule (NCAM) FG loop region. It promotes neuroplasticity and has shown cognitive-enhancing effects in research.

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Follistatin

Follistatin is a glycoprotein that inhibits myostatin, the protein responsible for limiting muscle growth. By blocking myostatin, follistatin can theoretically allow for increased muscle development beyond natural limits.

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Side-by-Side Comparison

AspectFGLFollistatin
MechanismBinds to FGFR1 (fibroblast growth factor receptor 1) to activate downstream signaling cascades that promote neurite outgrowth, synaptic plasticity, and neuronal survival.Binds to and neutralizes myostatin and activin, both of which are negative regulators of muscle mass. This removes the natural brake on muscle growth, allowing for enhanced hypertrophy.
Typical DosageResearch protocols have used subcutaneous doses ranging from 1-10mg. Intranasal administration also studied. Optimal dosing not established.Research protocols typically use 100-300mcg daily, though optimal dosing is not well established. Gene therapy approaches have also been studied.
AdministrationSubcutaneous injection or intranasal administration. Research compound with limited human dosing data.Subcutaneous injection. Different isoforms exist (FS344, FS315) with varying properties. Requires careful sourcing due to complexity.
Side EffectsLimited human data available. Animal studies show good tolerability.Limited human data. Theoretical concerns about effects on other organs where activin signaling is important.
Best For

Key Differences

Unique to FGL:

Unique to Follistatin:

Detailed Analysis

Commonalities

FGL and Follistatin are used for different purposes and have limited overlap in their applications.

Which Should You Choose?

Choose FGL for Cognitive Performance. Choose Follistatin for Muscle Growth.

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