Background: Physical activity has been found to play a role in cancer prevention. The purpose of this matchedcase-control study was to investigate the association between physical activity levels, water intake, constipationand colorectal cancer (CRC). Materials and
Methods: Two hundred and thirty-two patients diagnosed withCRC (125 male, 107 female) were enrolled in this case-control study. Cases were matched to 271 populationcontrols (137 male, 134 female).
Results: Drinking more than 4 cups of water daily decreased the risk of CRC by33-42%; however, this effect was non-significant. Having constipation was found to be a significant risk factorfor developing CRC with an OR=6.284 (95%CI=2.741-14.40). With reference to sedentary behavior, minimumactivity (600-3000 Metabolic Equivalents Task (MET)) had 43% protection against CRC and the level of HealthEnhancing Physical Activity OR was 0.58 (at 95%CI; 0.37-0.92). A significant negative association was foundbetween CRC and physical activity levels expressed as both METs and MET-hours/week (p for trend=0.017 and0.03, respectively). Among females, a significant trend of reduction in CRC by 62% was observed with increasingthe level of physical activity expressed in MET (p for trend=0.04).
Conclusions: The risk of CRC may be reducedby adopting a healthy lifestyle and practicing physically activity regularly, especially among females. Consumingadequate amounts of water and healthy bowel motility could also reduce the risk of CRC.