The effect of Synbiotics in humans on biomarkers of risk for colorectal cancer (CRC)

INTERVENTION: The aim of this study is to test the capacity of a synbiotic (Hi‐maize resistant starch + Bifidobacteria) administered in the diet to humans for improving the biomarkers associated with bowel health and reducing the potential risk of colorectal cancer. We will enlist 20 people in a random cross over design with an initial wash out period of 4 weeks (with no consumption of 'over the counter' products of Resistant Starch or Bifidobacteria) followed by three treatment phases, using the following variables: Synbiotic – resistant starch (RS) + Bifidobacteria. 4 wks Probiotic only – Bifidobacteria. 4 wks Prebiotic only ‐ resistant starch. 4 wks CONDITION: Bowel cancer PRIMARY OUTCOME: Faeces: 24 hour faecal samples for measures including carbohydrate fermentation products (short chain fatty acids), & microflora profile. Plasma: Measurement of short chain fatty acids (acetate, propionate and butyrate), blood DNA & serum cytokines. Rectal epithelium: Histological analysis of rectal epithelial which includes proliferation, apoptosis, cellularity, DNA adducts, MGMTase activity & DNA methylation. SECONDARY OUTCOME: Faeces: ; 24 hour faecal samples: Measures include: Faecal bulk, pH, protein fermentation products (N‐nitrosamines, phenols, cresols). INCLUSION CRITERIA: Healthy, with no active bowel disease, or with a previous history of adenoma removal.