A colon polyp and rectal bleeding

This page describes what two public sources say a colon polyp is. It does not sort one person's bleeding. ahem has not examined anyone and does not sell a treatment.

NIDDK last reviewed its definition page in July 2017. Opened October 28, 2026, it says colon polyps are growths on the lining of the colon and rectum, and that a person can have more than one. Most polyps are not cancerous. Some may turn into cancer over time. Removing polyps can help prevent colorectal cancer. On that page, colorectal cancer is the third leading cause of cancer death in the United States, a line NIDDK credits to the U.S. Preventive Services Task Force. Anywhere between 15 and 40 percent of adults may have colon polyps, and they are more common in men and older adults.

Mayo Clinic dates its polyp page September 24, 2025. It calls a colon polyp a small clump of cells on the lining of the colon. Most are harmless. Over time, some can turn into colorectal cancer. The most common precancerous type it names is an adenomatous polyp, often called an adenoma. It says healthcare professionals recommend removing adenomas so they do not grow larger or become cancerous. The page also separates polyps that rarely become cancer from polyps it calls precancerous. Hyperplastic polyps, which it says are common in the lower colon and rectum, are in the group that almost never turns into cancer.

NIDDK's symptoms page, also last reviewed in July 2017 and opened October 28, 2026, says most people with colon polyps do not have symptoms and can feel well. Mayo Clinic says colon polyps do not usually cause symptoms, which is why it calls screening important, and that polyps are often found during routine colorectal cancer screening.

When symptoms do show up, NIDDK lists bleeding from the rectum, which might be blood on underwear or on toilet paper after a bowel movement, blood in the stool, and feeling tired because of anemia and not enough iron. It says blood can make stool look black or can show up as red streaks. Mayo Clinic's symptom list includes a change in bowel habits such as constipation or diarrhea that lasts longer than a week, a change in stool color, more mucus in the stool, iron deficiency anemia with tiredness and shortness of breath, pain from a large polyp or cancer blocking part of the bowel, and rectal bleeding. The week count for a change in bowel habits is Mayo Clinic's, on the page checked October 28, 2026.

Mayo Clinic says rectal bleeding can be a sign of colon polyps, cancer, or other conditions, such as hemorrhoids or minor tears of the anus. NIDDK says many other health problems can also cause rectal bleeding, blood in the stool, and anemia. A streak of blood is also how hemorrhoid pages describe an internal hemorrhoid, and those pages still say to have the bleeding checked. That check is when rectal bleeding should be checked.

The difference these polyp pages add is that most polyps cause no feeling at all, and that finding and removing them is how both institutions describe preventing a later cancer. A hemorrhoid page is about swollen veins and a symptom that is already there. A polyp page is about a growth that may be silent until blood, black stool, or tiredness from slow blood loss shows up. Anemia from ongoing hemorrhoid bleeding is a separate, uncommon complication on complications the sources name. NIDDK's polyp page ties anemia to bleeding from the polyp. The two anemia sentences are about two different sources of blood loss.

NIDDK says a doctor will recommend screening for colorectal cancer starting at age 45 if you do not have health problems or other factors that make colorectal cancer more likely. If the risk is higher, screening may start younger and happen more often. If you are older than age 75, NIDDK says to talk with a doctor about whether to be screened. Those ages are on the definition page last reviewed in July 2017 and opened October 28, 2026. The page credits the task force recommendation updated May 18, 2021.

Mayo Clinic, on the page dated September 24, 2025, says to be screened regularly if you are age 45 or older, and also if you are younger than 45 and have medical conditions or a family history that increases risk. The shared starting age for people without those extra risks is 45. The older-than-75 conversation is NIDDK's sentence. Mayo Clinic's page opened the same day does not print 75.

Mayo Clinic's risk list also says diabetes increases polyp risk by 50 percent among all age groups, and that studies show three or more alcoholic drinks a day are linked with a higher chance of colon polyps. Those two figures are Mayo Clinic's, checked October 28, 2026. NIDDK's facts page lists age 45 or older, a family history of polyps or colorectal cancer, inflammatory bowel disease such as ulcerative colitis or Crohn's disease, obesity, and cigarette smoking. It does not print the 50 percent diabetes line.

NIDDK says to contact a doctor right away for bleeding from the rectum or blood in the stool. Mayo Clinic says to see a healthcare professional for belly pain, blood in the stool, a change in bowel habits that lasts longer than a week, or weight loss that happens without trying. The test both institutions describe for looking through the whole colon is a colonoscopy. What a hemorrhoid visit looks at first, including when a colonoscopy comes up, is on what a hemorrhoid exam checks.

Mayo Clinic says the earlier polyps are taken out, the less likely they are to become cancerous. NIDDK says removing polyps can help prevent colorectal cancer. Neither sentence is a promise about one polyp that has already been found. The pages also describe rare inherited patterns with many polyps. Those patterns are a reason for a clinician and, on Mayo Clinic's page, sometimes a genetic counselor. They are not a checklist for home use.