Final answer:
Red meat and certain fruits can alter the results of a fecal occult test by potentially causing false positives or negatives, and should be avoided before taking the test.
Step-by-step explanation:
Foods that can alter the results of a fecal occult test include red meat and certain fruits. An accurate result is crucial for gauging gastrointestinal health and detecting conditions that may involve blood in the stool. It is essential to avoid these foods before taking the test to prevent false positives or negatives. Dietary fiber, while important for digestion, does not typically affect fecal occult blood testing results. However, individuals should follow their healthcare provider's specific dietary recommendations prior to testing.