Also, direct the patient to avoid the following foods for two days before the test: No, red meat. The chicken and fish were also stopped. Peroxidase-rich vegetables like turnip, spinach, horseradish, mushrooms , broccoli , beans, cauliflower, oranges, banana, cantaloupe, and grapes. No raw fruits. Avoid Vitamin C , which causes a false negative reaction by inhibiting the peroxidase reaction. https://labpedia.net/stool-examination-part-35-stool-for-occult-blood-ob-fecal-occult-blood/