What foods can one eat before a colorectal cancer screening?

Generally none: Generally it is recommended you not eat solid food the day prior to your colonoscopy. It may be helpful to avoid salads and corn for 2-3 days.

Clear liquids only: If you are having a colonoscopy, the ultimate colorectal screening study, you will most likely be taking a strong cathartic and should take no solid food for 24 hours prior to the study. You should drink lots is water and clear liquids(liquids you can see through). You should avoid red liquids. I advise my patients to start the prep early in the day so they are not up all night!