Table 1.

Studies showing the effect of prebiotics on the gastrointestinal tract.

Prebiotic	Dose	Subjects	Main Results	Reference
FOS	6 g/day for 4 weeks	Patients with IBS	No therapeutic effect.	[99]
	20 g/day for 12 weeks	Patients with IBS	No therapeutic effect.	[100]
	5 g/day for 6 weeks	Patients with IBS	Improvement in IBS syndromes.	[102]
	15 g/day for 3 weeks	Patients with active ileocolonic Crohn’s disease	Crohn’s disease improvement.	[103]
	15 g/day for 4 weeks	Patients with Crohn’s disease	No clinical improvement in Crohn’s disease.	[104]
GOS	3.5 g/day for 12 weeks	Patients with IBS	Improvement in IBS syndromes.	[102]
Mixture of FOS and GOS	0.8 g/dL of a mixture of GOS and FOS, ratio 9:1 for 30 days	Healthy newborns	Improvement in gastric emptying and bowel motility.	[115]
	0.8 g/dL of a mixture of GOS and FOS, ratio 9:1 for 15 days	Healthy newborns	Improvement in gastric emptying and bowel motility.	[116]
Inulin-enriched FOS	20 g/day for 4 weeks	Patients with inactive and mild to moderately active Crohn’s disease	No clinical Improvement in Crohn’s disease.	[105]
	Raftilose® Synergy 1 + Bifidobacterium lactis Bb12, Lactobacillus rhamnosus GG	HT29 or CaCo-2 cells	Cell growth inhibition. As a result, this mixture can decrease the progression of colorectal cancer.	[119]
	Different doses	Rats with colon carcinogen	Long-chain inulin effects are dose-dependent on colorectal cancer.	[120]
	Synergy 1 + Bifidobacterium lactis Bb12, Lactobacillus rhamnosus GG	Colon cancer patients and polypectomized patients	Decrease in the progression of colorectal cancer.	[110]
Lactose	25 g daily for 15 days	Lactose malabsorbers	Improvement in lactose digestion.	[117]

FOS: Fructo-oligosaccharides; IBS: irritable bowel syndrome; and GOS: Galacto-oligosaccharides.