Read more: Health Symptoms That Are Serious Red Flags Pencil-thin poop could be a sign that there's a narrowing in your colon ...

According to Dueker, any noticeable alteration in your bowel habits could be a potential red flag (but, he stressed, is not ...

Writing for the Mayo Clinic, Dr Elizabeth Rajan said that “pencil thin” poop can rarely be a sign of irritable bowel syndrome (IBS). The pro says you should see your doctor if the change ...