Galactooligosaccharides (GOS)
A gentle prebiotic, similar to human milk, that supports a healthy infant and adult microbiome.
Also known as: GOS
Overview
Galactooligosaccharides (GOS) are a type of prebiotic fiber composed of galactose sugar chains. They are structurally similar to oligosaccharides found in human breast milk, which are crucial for establishing a healthy gut microbiome in infants. Like FOS, GOS is indigestible by humans and selectively stimulates the growth of beneficial Bifidobacteria and Lactobacilli in the colon. GOS is often considered gentler and better tolerated than other prebiotics like inulin or FOS.
Key Benefits
Strong Bifidogenic Effect
Very effective at increasing the population of beneficial Bifidobacteria.
Well-Tolerated
Generally produces less gas and bloating compared to FOS or inulin at similar doses.
Supports Infant Gut Health
Added to many infant formulas to mimic the prebiotic effects of breast milk.
Dosage & How to Take
2-7 grams per day.
| Purpose | Dose | Notes |
|---|---|---|
| Starting dose | 1-2 grams/day | Increase slowly over a week or two. |
| Typical dose | 4-5 grams/day |
Best Time to Take
Can be taken anytime.
With or Without Food
Can be mixed into food or drinks.
Forms & Bioavailability
| Form | Absorption | Best For | Notes |
|---|---|---|---|
| Powder/Syrup | N/A (local effect) | Easy dosing | Derived from lactose, so may not be suitable for strict vegans. |
Side Effects & Safety
Common
- Mild gas or bloating, but less than other prebiotics
Rare
- None known
Contraindications
- Galactosemia (a rare genetic disorder)
Interactions
GOS is a food-based fiber and has no known drug interactions.
Scientific Research
GOS and Gut Microbiota
A randomized controlled trial showed that 5.5g of GOS per day for 6 weeks significantly increased Bifidobacteria and improved anxiety scores in young adults.
Food Sources
Frequently Asked Questions
Medical Disclaimer
This content is for educational and informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare professional before starting any supplement regimen, especially if you have pre-existing health conditions or are taking medications. The statements on this page have not been evaluated by the Food and Drug Administration.