Most people have incorrect assumptions about hemorrhoids. Alexis Grucela, MD, assistant professor in the Division of Colorectal Surgery in NYU Langone’s Department of Surgery, explains to Prevention how hemorrhoids are not only common, but a normal part of the gastrointestinal system. Hemorrhoids are anal tissue that gives extra support in the anal canal. They can be external and internal, and are often not a harmful medical issue.

“It's only when they become symptomatic that people start noticing them,” Dr. Grucela says. “Usually, they just do their job.”

Symptomatic hemorrhoids are what most people associate with hemorrhoids. Approximately 1 in 20 Americans have symptomatic hemorrhoids, and while they can be uncomfortable, they are usually not very harmful to one’s health. Dr. Grucela suggests talking to a doctor about blood in the stool, in case the symptoms are indicative of something more serious.

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