Overview
Galactose-based prebiotic.
- Endogenously produced or biosynthesized molecule
- Standardized pharmaceutical- or food-grade supplement
- Combined with cofactors that improve absorption or activity
- Capsule or softgel
- Powder
- Sublingual or buccal
- Liposomal liquid
Mechanism of action
Selectively feeds Bifidobacteria.
- · Selectively feeds Bifidobacteria
Effects on the body
Organ system effects
GOS (Galactooligosaccharides) influences gut motility, mucosal integrity, or microbial balance in the GI tract.
GOS (Galactooligosaccharides) acts on central nervous system targets implicated in attention, memory, and neuroprotection.
Evidence-based benefits
Reduces stress cortisol
Moderate evidencePotential side effects
- · Bloating
Drug interactions
Supplement interactions
- Multi-strain probioticSupports microbiome diversity and barrier integrity.
- L-glutamineSubstrate for enterocyte energy and tight-junction maintenance.
- Omega-3 (EPA/DHA)Membrane fluidity and neuronal signaling support.
No specific avoidances listed.
Dosing & bioavailability
Where to buy
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Third-party testedIndependently verified GOS (Galactooligosaccharides) — look for USP, NSF, or Informed Sport seals on the label for purity and dose accuracy.GOS (Galactooligosaccharides) third party tested NSF
CapsulesPre-measured GOS (Galactooligosaccharides) capsules — easiest for travel and consistent daily dosing without scoops or scales.GOS (Galactooligosaccharides) capsules
PowderBulk unflavored GOS (Galactooligosaccharides) powder — best cost-per-gram and flexible dosing for stacking or mixing into drinks.GOS (Galactooligosaccharides) powder unflavored
Best sellersMost-purchased GOS (Galactooligosaccharides) products on Amazon — a quick way to see what's reviewed widely before you commit.GOS (Galactooligosaccharides) best sellerScientific evidence8Show studiesHide studies
GOS for cortisol
Schmidt K, et al.
45 healthy adults
Reduced waking cortisol.
PubMed: GOS (Galactooligosaccharides) — Reduces stress cortisol
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