Table of ContentsView AllTable of ContentsAnatomyFunctionSymptomsColon Health

Table of ContentsView All

View All

Table of Contents

Anatomy

Function

Symptoms

Colon Health

The colon (also known as the large intestine) is a U-shaped, segmented tube made of muscle that is located below the stomach and connects to the rectum at the end of the colon. The colon and rectum are about 2 meters (6.5 feet) long.

The colon works alongside the stomach andsmall intestineto remove stool and maintain fluid and electrolyte balance. Understanding how the colon works is the first step to keeping your colon healthy.

The colon makes up most of the large intestine, beginning with where it connects to the small intestine, called thececum. The five other sections of the colon include the following:

The cecum is the widest part of your colon and is approximately 5 centimeters (cm) long (almost 2 inches). It’s part of what’s also called the proximal, or right-sided, colon, including the ascending and transverse portions.

Colon CancerColon cancer can occur in any section of the colon.About 20% occur in the cecum.About 20% to 25% percent originate in the distal colon (descending and sigmoid sections)About 25% to 30% occur in the rectum.

Colon Cancer

Colon cancer can occur in any section of the colon.About 20% occur in the cecum.About 20% to 25% percent originate in the distal colon (descending and sigmoid sections)About 25% to 30% occur in the rectum.

Colon cancer can occur in any section of the colon.

Atortuous colonis one that is longer than normal. In this relatively rare condition, the colon has extra twists and turns to be able to fit in the abdomen.

The majority of the nutrients you eat are absorbed in the small intestine well before the “food” reaches your colon. Thecolon’s main functionis to receivechyme, the mix of digested food from the small intestine, and further digest it into a firm stool that passes from the body.

The colon must reabsorb water and electrolytes to form a stool. This is why, when you are dehydrated, you can get constipated and your stool may become hard and difficult to pass. The colon needs to pull more fluid from the stool for your body to use.

It is possible to live without a colon. People have portions of their colon removed in surgery, calledsurgical bowel resection, to treat several conditions includingcolon cancer. However, all 6 feet of your colon serve a purpose.

Layers of the Colon

The colon is about 6 feet long and is composed of four layers, each with a specific function. Starting at the innermost layer of the colon, the layers include the following:

When adiagnosis of colon canceris made, the pathologist will determine what layer the cancer has reached (such as the innermost or outermost layer) to help determine the staging of the cancer.

The majority of colorectal cancers will start in the innermost layer, called the mucosa, and spread toward the outermost layer, or the serosa, if untreated.

Signs of a Colon Problem

Symptoms that might indicate a problem with your colon include:

How to Keep Your Colon Healthy

Many lifestyle-related factors have been linked to colorectal cancer. More than half of all colorectal cancers are linked to risk factors that can be changed, such as:

Colon Cancer RiskCancers of thecolonandrectum, often grouped together as colorectal cancer, most often start as growths called colon polyps. The presence of certain polyps, such asadenomas, present a higher risk of cancer.Factors including genetics, underlying health conditions, and lifestyle habits can increase the risk.Colonoscopy screenings are an important tool for identifying and removing polyps.

Colon Cancer Risk

Cancers of thecolonandrectum, often grouped together as colorectal cancer, most often start as growths called colon polyps. The presence of certain polyps, such asadenomas, present a higher risk of cancer.Factors including genetics, underlying health conditions, and lifestyle habits can increase the risk.Colonoscopy screenings are an important tool for identifying and removing polyps.

Cancers of thecolonandrectum, often grouped together as colorectal cancer, most often start as growths called colon polyps. The presence of certain polyps, such asadenomas, present a higher risk of cancer.

Factors including genetics, underlying health conditions, and lifestyle habits can increase the risk.

Colonoscopy screenings are an important tool for identifying and removing polyps.

Summary

The colon, or large intestine, is the part of your gastrointestinal system that moves digested food from the small intestine and out of the body. Different segments make up the colon, beginning with the cecum and ending with the rectum, which will release stool to pass from the anus.

11 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.American Cancer Society.What Is Colorectal Cancer?Harkins JM, Sajjad H.Anatomy, abdomen and pelvis, sigmoid colon. StatPearls.Wu W, Yang J, Li D, Huang Q, Zhao F, Feng X,et al.Competitive Risk Analysis of Prognosis in Patients With Cecum Cancer: A Population-Based Study.Cancer Control. 2021 Jan-Dec;28:1073274821989316. doi: 10.1177/1073274821989316.Carethers JM.Risk factors for colon location of cancer.Transl Gastroenterol Hepatol.2018;3:76. doi:10.21037/tgh.2018.09.15.American Cancer Society.Colorectal cancer signs and symptoms.American Cancer Society.Colorectal cancer risk factors.American Institute of Cancer Research.Limit consumption of red meat and processed meat.American Cancer Society.Can colorectal cancer be prevented?Kunzmann AT, Coleman HG, Huang WY, Kitahara CM, Cantwell MM, Berndt SI.Dietary fiber intake and risk of colorectal cancer and incident and recurrent adenoma in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial.Am J Clin Nutr. 2015;102(4):881-90. doi: 10.3945/ajcn.115.113282.Aykan NF.Red meat and colorectal cancer.Oncol Rev. 2015;9(1):288. doi:10.4081/oncol.2015.288.Rossi M, Jahanzaib anwar M, Usman A, Keshavarzian A, Bishehsari F.Colorectal cancer and alcohol consumption-populations to molecules.Cancers (Basel). 2018;10(2). doi:10.3390/cancers10020038.Additional ReadingAmerican Cancer Society.American Cancer Society’s Complete Guide to Colorectal Cancer. Clifton Fields, NE: American Cancer Society.Witmer, L.Clinical anatomy of the large intestine.Harvard School of Public Health. (n.d.).Protein: What Should I Eat?

11 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.American Cancer Society.What Is Colorectal Cancer?Harkins JM, Sajjad H.Anatomy, abdomen and pelvis, sigmoid colon. StatPearls.Wu W, Yang J, Li D, Huang Q, Zhao F, Feng X,et al.Competitive Risk Analysis of Prognosis in Patients With Cecum Cancer: A Population-Based Study.Cancer Control. 2021 Jan-Dec;28:1073274821989316. doi: 10.1177/1073274821989316.Carethers JM.Risk factors for colon location of cancer.Transl Gastroenterol Hepatol.2018;3:76. doi:10.21037/tgh.2018.09.15.American Cancer Society.Colorectal cancer signs and symptoms.American Cancer Society.Colorectal cancer risk factors.American Institute of Cancer Research.Limit consumption of red meat and processed meat.American Cancer Society.Can colorectal cancer be prevented?Kunzmann AT, Coleman HG, Huang WY, Kitahara CM, Cantwell MM, Berndt SI.Dietary fiber intake and risk of colorectal cancer and incident and recurrent adenoma in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial.Am J Clin Nutr. 2015;102(4):881-90. doi: 10.3945/ajcn.115.113282.Aykan NF.Red meat and colorectal cancer.Oncol Rev. 2015;9(1):288. doi:10.4081/oncol.2015.288.Rossi M, Jahanzaib anwar M, Usman A, Keshavarzian A, Bishehsari F.Colorectal cancer and alcohol consumption-populations to molecules.Cancers (Basel). 2018;10(2). doi:10.3390/cancers10020038.Additional ReadingAmerican Cancer Society.American Cancer Society’s Complete Guide to Colorectal Cancer. Clifton Fields, NE: American Cancer Society.Witmer, L.Clinical anatomy of the large intestine.Harvard School of Public Health. (n.d.).Protein: What Should I Eat?

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

American Cancer Society.What Is Colorectal Cancer?Harkins JM, Sajjad H.Anatomy, abdomen and pelvis, sigmoid colon. StatPearls.Wu W, Yang J, Li D, Huang Q, Zhao F, Feng X,et al.Competitive Risk Analysis of Prognosis in Patients With Cecum Cancer: A Population-Based Study.Cancer Control. 2021 Jan-Dec;28:1073274821989316. doi: 10.1177/1073274821989316.Carethers JM.Risk factors for colon location of cancer.Transl Gastroenterol Hepatol.2018;3:76. doi:10.21037/tgh.2018.09.15.American Cancer Society.Colorectal cancer signs and symptoms.American Cancer Society.Colorectal cancer risk factors.American Institute of Cancer Research.Limit consumption of red meat and processed meat.American Cancer Society.Can colorectal cancer be prevented?Kunzmann AT, Coleman HG, Huang WY, Kitahara CM, Cantwell MM, Berndt SI.Dietary fiber intake and risk of colorectal cancer and incident and recurrent adenoma in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial.Am J Clin Nutr. 2015;102(4):881-90. doi: 10.3945/ajcn.115.113282.Aykan NF.Red meat and colorectal cancer.Oncol Rev. 2015;9(1):288. doi:10.4081/oncol.2015.288.Rossi M, Jahanzaib anwar M, Usman A, Keshavarzian A, Bishehsari F.Colorectal cancer and alcohol consumption-populations to molecules.Cancers (Basel). 2018;10(2). doi:10.3390/cancers10020038.

American Cancer Society.What Is Colorectal Cancer?

Harkins JM, Sajjad H.Anatomy, abdomen and pelvis, sigmoid colon. StatPearls.

Wu W, Yang J, Li D, Huang Q, Zhao F, Feng X,et al.Competitive Risk Analysis of Prognosis in Patients With Cecum Cancer: A Population-Based Study.Cancer Control. 2021 Jan-Dec;28:1073274821989316. doi: 10.1177/1073274821989316.

Carethers JM.Risk factors for colon location of cancer.Transl Gastroenterol Hepatol.2018;3:76. doi:10.21037/tgh.2018.09.15.

American Cancer Society.Colorectal cancer signs and symptoms.

American Cancer Society.Colorectal cancer risk factors.

American Institute of Cancer Research.Limit consumption of red meat and processed meat.

American Cancer Society.Can colorectal cancer be prevented?

Kunzmann AT, Coleman HG, Huang WY, Kitahara CM, Cantwell MM, Berndt SI.Dietary fiber intake and risk of colorectal cancer and incident and recurrent adenoma in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial.Am J Clin Nutr. 2015;102(4):881-90. doi: 10.3945/ajcn.115.113282.

Aykan NF.Red meat and colorectal cancer.Oncol Rev. 2015;9(1):288. doi:10.4081/oncol.2015.288.

Rossi M, Jahanzaib anwar M, Usman A, Keshavarzian A, Bishehsari F.Colorectal cancer and alcohol consumption-populations to molecules.Cancers (Basel). 2018;10(2). doi:10.3390/cancers10020038.

American Cancer Society.American Cancer Society’s Complete Guide to Colorectal Cancer. Clifton Fields, NE: American Cancer Society.Witmer, L.Clinical anatomy of the large intestine.Harvard School of Public Health. (n.d.).Protein: What Should I Eat?

American Cancer Society.American Cancer Society’s Complete Guide to Colorectal Cancer. Clifton Fields, NE: American Cancer Society.

Witmer, L.Clinical anatomy of the large intestine.

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