1. Decreased frequency: A sudden decrease in the frequency of passing gas may indicate a blockage in the intestines, potentially caused by colorectal cancer. This can lead to excessive bloating.
2. Foul odor: Flatulence with a bloody or foul odor should not be dismissed as hemorrhoids. Colon cancer can cause bleeding and produce a distinct odor when gas or feces pass through.
3. Rotten egg smell: If gas smells like rotten eggs, it could be due to colon cancer causing obstruction and increased gas production.
4. Increased frequency: An abrupt increase in passing gas can also be a warning sign of colon cancer, as an imbalance of gut microbiota can lead to increased gas production.