• Faecal calprotectin concentrations (marker of local inflammation) [ Time Frame: 12 years (on average) ]
• Serum high-sensitivity C-Reactive Protein concentrations (marker of systemic inflammation) [ Time Frame: 12 years (on average) ]

• Gut microbiota (analysed in stool samples) [ Time Frame: 12 years (on average) ]
  Abundance and diversity of the gut microbiota assessed in stool samples
• Faecal short-chain fatty acid concentrations [ Time Frame: 12 years (on average) ]
  Concentrations and proportions of short-chain fatty acids e.g. acetate, propionate and butyrate
• DNA methylation in rectal mucosal biopsies(% methylation) [ Time Frame: 12 years (on average) ]
  Target gene and global methylation (LINE-1) in rectal mucosal biopsies
• Target gene expression in rectal mucosal biopsies [ Time Frame: 12 years (on average) ]
  Expression of genes related to inflammation and the WNT signalling pathway in rectal mucosal biopsies
• microRNA expression in rectal mucosal biopsies [ Time Frame: 12 years (on average) ]
  Expression of microRNAs in rectal mucosal biopsies
• Colonic crypt cell proliferative state [ Time Frame: 12 years (on average) ]
  Total number and distribution of proliferating cells in rectal mucosal crypts
• Colonic crypt cell dimensions [ Time Frame: 12 years (on average) ]
  Height (length) and width rectal mucosal crypts
• Markers of mitochondrial function and structure in rectal mucosal biopsies [ Time Frame: 12 years (on average) ]
  Markers of mitochondrial function and structure in rectal mucosal biopsies such as oxidative phosphorylation proteins, namely complex I and IV
• Parathyroid hormone in plasma [ Time Frame: 12 years (on average) ]
• 25-hydroxy vitamin D concentrations in serum [ Time Frame: 12 years (on average) ]
• Vitamin B12 concentrations in serum [ Time Frame: 12 years (on average) ]
• Folate concentrations in serum [ Time Frame: 12 years (on average) ]
• Triglycerides in plasma [ Time Frame: 12 years (on average) ]
• HDL cholesterol in plasma [ Time Frame: 12 years (on average) ]
• LDL cholesterol in plasma [ Time Frame: 12 years (on average) ]
• Total cholesterol in plasma [ Time Frame: 12 years (on average) ]
• Glucose in plasma [ Time Frame: 12 years (on average) ]
• HbA1c in whole blood [ Time Frame: 12 years (on average) ]

• Timed-up and go test time [ Time Frame: 12 years (on average) ]
• Hand grip strength using dynamometer [ Time Frame: 12 years (on average) ]
• Heel bone density using Achilles heel ultrasound device [ Time Frame: 12 years (on average) ]
• Body weight in kg [ Time Frame: 12 years (on average) ]
• BMI in kg/m2 (calculated from height and weight) [ Time Frame: 12 years (on average) ]
• Height in cm [ Time Frame: 12 years (on average) ]
• Body fat percentage [ Time Frame: 12 years (on average) ]
  Measured using Tanita Bioimpedance scales
• Habitual dietary intake assessed using Food Frequency Questionnaire [ Time Frame: 12 years (on average) ]
• Physical activity levels assessed using Lifestyle Questionnaire [ Time Frame: 12 years (on average) ]
• Physical activity levels assessed using accelerometer [ Time Frame: 12 years (on average) ]
• Sedentary behaviour assessed using Lifestyle Questionnaire [ Time Frame: 12 years (on average) ]

The BORICC Follow-Up (BFU) Study builds on the findings from the BORICC Study where the investigators observed associations between age and nutritional factors, including selenium and folate, and biomarkers of colorectal health.

The BFU Study will investigate the relationships between ageing (12+ years) and such biomarkers longitudinally. It is anticipated that the project will produce novel data on (i) changes in biomarkers of colorectal cancer risk with age and (ii) the effects of obesity and lifestyle factors on biomarkers of colorectal cancer risk. These biomarkers include differentially expressed proteins, DNA methylation markers and inflammation markers.

• Healthy
  Participants recruited to the healthy arm of the BORICC Study (BORICC1) at baseline.
• Polyp
  Participants recruited to the polyp arm of the BORICC Study (BORICC2) at baseline, with a prior history of polyps.

Inclusion Criteria:

• Took part in the BORICC Study at baseline (recruited 2005/6)

Exclusion Criteria:

• Unable to travel to the hospital to attend study visit
• Unable to provide informed written consent