Can sudden intolerance to certain foods be an early sign of colon cancer?

Sometimes, early colon cancer can cause subtle digestive changes that make the body unusually sensitive to foods it previously handled well—especially high-fiber foods or greasy meals. This happens because tumors can partially narrow the colon, causing bloating, cramps, or discomfort after eating. While food intolerance has many causes, new or persistent sensitivity should be evaluated if it doesn’t improve.