Table 4.

Prevention of Colorectal cancer (CRC) Using Various Prebiotics in Human Clinical Trials.

Reference	Type of Study	Prebiotic	Probiotic	Mechanism of Action
[35]	Research Human, A randomized, double-blind, no-treatment parallel control, clinical trial study involving 140 perioperative patients (90 men and 50 women, aged 40–75 y)	30 g prebiotic supplement (Hangzhou Niuqu Biotech Co., Hainengbo, China) containing fructooligosaccharide (25%), xylooligosaccharide (25%), polydextrose (25%), and resistant dextrin (25%)		✓Improved serum immunologic indicators (significantly increased IgG and IgM levels preoperatively. Postoperatively the supplementation enhanced the levels of IgG, IgA, total B lymphocytes (CD19+), and suppressor/cytotoxic T cells (CD3+CD8+). ✓Prebiotics increased the level of transferrin as prebiotics relieve the inflammatory reaction of the body, resulting in increased transferrin level. ✓Altered the intestinal microbial community at the at the genus level: a decline in Bacteroidetes in the prebiotic/pre group. The abundance of Bifidobacterium and Enterococcus increased significantly in the prebiotic/pre group. It is proposed that Bifidobacteria prevent against CRC by regulating intestinal microbiota, enhancing host immune response, and degrading potential carcinogens. ✓Increased the abundance of intestinal opportunistic pathogens and harmless strains of Escherichia species.
[36]	Cohort postmenopausal women in the United States	Prebiotic fiber supplements categorized as soluble or insoluble		The findings do not support use of prebiotic supplements to reduce risk of colorectal cancer or colorectal cancer–specific mortality among postmenopausal women.