Evidence Based
This article is objectively based on relevant scientific literature, written by experienced medical writers, and fact-checked by a team of degreed medical experts.
Our team of registered dietitian nutritionists and licensed medical professionals seek to remain objective and unbiased while preserving the integrity of any scientific debate.
The articles contain evidence-based references from approved scientific sites. The numbers* in parentheses (*1,2,3) will take you to clickable links to our reputable sources.
Sigmoid Colon: What Is It & What Does It Do In 2023

The sigmoid colon’s anatomy is a vital part of the large intestines. It’s beneficial to understand the sigmoid colon and its primary function in the digestive system, which is to absorb water and remove waste through the large intestine.
In this article, we’ll look at the functions of the digestive system sigmoid colon. Also, we’ll highlight why probiotics and probiotic foods benefit colon health. Let’s get started.
Key Takeaway
- The sigmoid colon is the very last stretch of the colon before you reach the rectum.
- It is essentially the lower back abdominal area with the pelvis including the ascending colon, transverse colon, descending colon, sigmoid colon, and rectum.
- The sigmoid colon helps your body water and electrolyte absorption, absorbing remaining nutrients, forming fecal matter, and so on.
- Some of the issues that can affect your sigmoid colon are diverticulosis, sigmoid volvulus, colonic polyps, etc.
- Keep your colon healthy through diet changes, lifestyle modifications, and medical interventions.
What Is The Sigmoid Colon?
It’s the very last stretch of the colon before you reach the rectum. It links the descending colon to the rectum in the shape of an S. Its significant role is to create and store fecal waste while taking in water and any residual nutrients from all your meals. By helping bowel movements, this body part is vital to the entire human anatomy.
A few of the diseases that can hurt this area. Maintaining digestive health and treating related dire medical disorders requires an understanding of the colon.
Featured Partner

Low-Calorie
Non-GMO
Vegan-friendly
Get Blown Away By Expert-Crafted Formula
Learn More About Colon Broom – one of the quality supplements promoting regular bowel movements, alleviates bloating, and supports healthy cholesterol levels.
Where Is The Sigmoid?
The human colon is part of the retroperitoneal structure, essentially the lower back abdominal area with the pelvis. The entire colon is about five feet long when stretched out and divided into five main segments.
These five segments[1] are:
Ascending Colon
This section of the large intestines begins at the cecum. The cecum is the pouch-like structure at the junction of the small intestine and large intestine. The ascending colon moves upwards on the right side of the abdominal cavity.
Transverse Colon
The transverse colon is positioned horizontally across the upper abdomen. It begins from the ascending colon’s right end and extends towards the left side.
Descending Colon
On the left side of the belly, this section of the colon pushes food downward. The descending colon starts at the transverse colon’s terminus and travels to the sigmoid.
Sigmoid Colon
The final section of the large intestine, commonly known as the distal colon, is the sigmoid. This section is an S-shaped portion that connects the descending colon and rectum. The sigmoid colon’s location is within the lower abdominal cavity. Sigmoid is from the Greek letter sigma, which mirrors its shape.
Rectum
The rectum is the final part of the large intestine. It is responsible for storing formed fecal matter before ridding it from the body. This waste leaves the body through the anal canal when emptying your bowel.
A delicate enteric nervous system[2] of connective tissue, smooth muscles, nerve supply, venous drainage, and arterial supply surrounds the gastrointestinal tract. These systems offer the sigmoid support for proper functioning.
The sigmoid colon derives its blood supply from the inferior mesenteric artery. The nerve supply is from the pelvic splanchnic nerves,[3] helping you feel abdominal cavity pain.
Sigmoid Colon Function
What does colon do? We have already established that the sigmoid is the last section with essential roles. Here are all its roles:
- Water and electrolyte absorption: This part of the colon’s primary function[4] is allowing water from the digested food to enter the bloodstream. A healthy sigmoid colon helps maintain fluid and electrolyte balance.
- Absorbing remaining nutrients: Alongside water, the sigmoid colon absorbs essential nutrients from the remaining digested food. This ensures that the body maximizes nutrient uptake before waste elimination.
- Forming fecal matter: As the digested food matter travels through the colon, the sigmoid section aids in consolidating waste[5] in liquid and solid matter. This process is called peristalsis.[6]
- Storing fecal waste: This colon segment is also a reservoir, temporarily storing the formed fecal matter until it is ready for elimination.
- Facilitating bowel movements: When the fecal matter accumulates, the sigmoid colon contracts and pushes waste downwards. This prompts the urge for a bowel movement.
Some Common Sigmoid Colon Problems
The sigmoid colon is essential as it absorbs necessary water and nutrients. So having any infection or disease here can be detrimental. Here are some of the issues that can affect your colon:
Diverticulosis
Diverticulosis in the colon occurs[7] when small pouches form in the intestinal walls due to increased pressure. This diverticula in the sigmoid potentially leads to inflammation or infection.
A low-fiber diet, muscle tissue weakness, age, genetics, and lifestyle factors contribute to its development. diet[8] and a healthy lifestyle can lower the risk of diverticular disease.
Sigmoid Volvulus
This is a digestive tract condition where a portion of the intestine twists upon itself, obstructing the blood supply and severe abdominal pain.
One contributing factor is chronic constipation which heightens the risk of sigmoid volvulus.[9] The treatment includes detorsion[10] surgery to fix the colon and accompanying dietary changes. A high-fiber diet with plenty of water can help you prevent constipation.
Colonic Polyps
These are abnormal growths in the large intestine lining. They may be benign but can sometimes be a cancer precursor[11] if you do not treat them. Although the root cause of these polyps is still under scrutiny, there are risk factors.
These risk factors include age, a high-fat, low-fiber diet, and family history. Treatment[12] of these colon polyps may include the elimination of the growths to hinder potential cancer growth.
Inflammatory Bowel Disease
Chronic inflammation of the gastrointestinal tract, including ulcerative colitis[13] and Crohn’s disease,[14] impacts the colon. Surgery, medications, and dietary changes are all possible treatments.
Sigmoid Colon Cancer
This is the development of malignant cells in the colon. Colon sigmoid cancer’s cause is still yet to be uncovered. However, treatment may involve a sigmoidectomy[15] or a sigmoid colostomy[16] to remove the cancerous tissue.
A sigmoidectomy removes part of the colon, while a colostomy creates an opening for stool elimination outside the body. You may also need to follow up with chemotherapy, radiation, or targeted therapies to kill the remaining cancer cells to avoid recurrence.
Constipation
Constipation is characterized by difficulty passing stool due to reduced bowel movements, which can affect the sigmoid. A highly fibrous diet[17] may help you alleviate this condition.
Colonic Distension
This is the abnormal swelling or enlargement of the colon. It is often a result of trapped gas, fluid, stool, or a blockage within the colon. Colonic distension[18] can result in signs and symptoms like discomfort, bloating, pain in the abdomen, and changes in bowel habits.
In severe situations, it may result in consequences like intestinal obstruction or rupture, necessitating emergency medical care. The underlying reason will determine the best treatment for colonic distension.
Please note that none of these digestive conditions should be self-diagnosed. Getting professional medical care and attention for long-term solutions is always the best practice. Do this for all cases, whether it is constipation, Crohn’s disease, or any other issue.
How To Keep Your Colon Healthy
The colon is a vital organ that helps our body complete digestion, so how do you take care of it?
Here is how:
Diet Changes
- Consume gut-healing foods rich in fiber for regular bowel movements. You should also use probiotic foods and supplements for added nutrition and to prevent constipation and other digestive issues. Probiotics promote a healthy balance of gut bacteria,[19] aiding digestion and reducing inflammation[20] in the sigmoid colon.
- Stay hydrated to enhance water absorption in the large intestine.
Lifestyle Modifications
- Ensure you are physically active to support your digestive health and help prevent constipation.
- Stay away from harmful habits like smoking and alcohol drinking to minimize colon-related risks.
- Manage stressful events to keep your bowel habits healthy.
Medical Interventions
- If predisposed to colon issues, undergo regular screenings, especially if you are over 50. This helps encourage early detection to remove polyps or colon cancer.
- Sustain a healthy weight and avoid popularized diets to mitigate obesity-related effects on the digestive system.
- Use all medication, supplements, and superfoods as per your doctor’s advice.
Conclusion
The sigmoid colon, a crucial portion of the large intestine, absorbs the remaining water and nutrients from the foods we eat and excretes waste. It must be in excellent condition to ensure healthy digestion, where all digestive enzymes do their jobs.
Your digestive health may deteriorate if there is an issue due to colon inflammation or disease. Luckily, now that you know this colon, you can take proactive steps to minimize gut health issues. These include regular screenings, a gut health fiber-rich diet, regular exercise, and supplementation of superfoods.
Taking care of your colon health is essential and relatively simple. Please embrace a more conscious approach to a healthy gut now that you have that information.
Frequently Asked Questions
In some cases of severe sigmoid colon conditions like cancer or recurrent volvulus, surgical removal of the sigmoid colon may be required.
Available tests include a colonoscopy, sigmoidoscopy, computerized tomography scan, barium enema, and biopsy to diagnose and evaluate conditions affecting the sigmoid colon.
Signs may include abdominal pain, bloating, changes in bowel habits, rectal bleeding, and unexplained weight loss.
Sigmoid colon pain is typically felt in the lower left side of the abdomen, where the sigmoid colon is located. If you experience symptoms of sigmoid colon disease, contact your doctor.
The sigmoid colon is approximately 35-40 centimeters long.
+ 20 sources
Health Canal avoids using tertiary references. We have strict sourcing guidelines and rely on peer-reviewed studies, academic researches from medical associations and institutions. To ensure the accuracy of articles in Health Canal, you can read more about the editorial process here
- Mahadevan, V. (2020). Anatomy of the caecum, appendix and colon. [online] 38(1), pp.1–6. doi:https://doi.org/10.1016/j.mpsur.2019.10.017.
- Fleming, M., Ehsan, L., Moore, S.R. and Levin, D.E. (2020). The Enteric Nervous System and Its Emerging Role as a Therapeutic Target. [online] 2020, pp.1–13. doi:https://doi.org/10.1155/2020/8024171.
- Ofelia-Costina Goidescu, Iulian-Alexandru Dogaru, Mihaly Enyedi, Octavian Enciu, Daniela-Elena Gheoca Mutu and Florin-Mihail Filipoiu (2022). Infantile Haemangioma – Elaboration and Piloting a Specific Quality of Life Questionnaire. [online] 17(3), pp.576–582. doi:https://doi.org/10.26574/maedica.2022.17.3.576.
- Kiela, P.R. and Ghishan, F.K. (2016). Physiology of Intestinal Absorption and Secretion. [online] 30(2), pp.145–159. doi:https://doi.org/10.1016/j.bpg.2016.02.007.
- Annelies Verbiest, Palle Bekker Jeppesen, Joly, F. and Vanuytsel, T. (2023). The Role of a Colon-in-Continuity in Short Bowel Syndrome. [online] 15(3), pp.628–628. doi:https://doi.org/10.3390/nu15030628.
- Ma, A., Venugopal, S. and Jung, R. (2021). Engaging biological oscillators through second messenger pathways permits emergence of a robust gastric slow-wave during peristalsis. [online] 17(12), pp.e1009644–e1009644. doi:https://doi.org/10.1371/journal.pcbi.1009644.
- Rezapour, M., Ali, S. and Stollman, N. (2018). Diverticular Disease: An Update on Pathogenesis and Management. [online] 12(2), pp.125–132. doi:https://doi.org/10.5009/gnl16552.
- Aune, D., Sen, A., Norat, T. and Elio Riboli (2019). Dietary fibre intake and the risk of diverticular disease: a systematic review and meta-analysis of prospective studies. [online] 59(2), pp.421–432. doi:https://doi.org/10.1007/s00394-019-01967-w.
- Brian, Vigutto, G., Tan, E., Harry van Goor, Bendinelli, C., Fikri Abu-Zidan, Rao Ivatury, Sakakushev, B., Isidoro Di Carlo, Sganga, G., Maier, R.V., Coimbra, R., Ari Leppäniemi, Litvin, A., Dimitrios Damaskos, Richard Ten Broek, Biffl, W., Salomone Di Saverio, Belinda De Simone and Ceresoli, M. (2023). WSES consensus guidelines on sigmoid volvulus management. [online] 18(1). doi:https://doi.org/10.1186/s13017-023-00502-x.
- Necattin Firat, Baris Mantoglu, Ozdemir, K., Muhtaroğlu, A., Akin, E., Fehmi Çelebi and Fatih Altintoprak (2020). Endoscopic Detorsion Results in Sigmoid Volvulus: Single-Center Experience. [online] 2020, pp.1–5. doi:https://doi.org/10.1155/2020/1473580.
- Huang, E. and Sarin, A. (2016). Colonic Polyps: Treatment. [online] 29(04), pp.306–314. doi:https://doi.org/10.1055/s-0036-1584090.
- Liu, Z., Jiang, L., Chan, F.H.Y., Michael Ka-Wah Li and Fan, J. (2020). Combined endo-laparoscopic surgery for difficult benign colorectal polyps. [online] 11(3), pp.475–485. doi:https://doi.org/10.21037/jgo.2019.12.11.
- Ungaro, R.C., Saurabh Mehandru, Allen, P.B., Laurent Peyrin-Biroulet and Colombel, J.-F. (2017). Ulcerative colitis. [online] 389(10080), pp.1756–1770. doi:https://doi.org/10.1016/s0140-6736(16)32126-2.
- Andrey Kotzev, Lachesar Tanchev, Encheva, L., Nikolay Kovachev and T Betova (2018). Sigmoidouterine Fistula in Crohn’s Disease: A First Case Report. [online] doi:https://doi.org/10.1093/ibd/izy352.
- Hou, H.-P. and Gui, P.-G. (2021). Effect of sigmoidectomy in treating sigmoid colon cancer. [online] 100(3), pp.e23914–e23914. doi:https://doi.org/10.1097/md.0000000000023914.
- Wang, F.-B., Pu, Y., Zhong, F., Liu, X., Yang, Z.-X. and Chen, X. (2015). Laparoscopic permanent sigmoid stoma creation through the extraperitoneal route versus transperitoneal route. [online] 36(2), pp.159–163. doi:https://doi.org/10.15537/smj.2015.2.10203.
- Yang, J., Wang, H.-P., Zhou, L. and Xu, C.-F. (2012). Effect of dietary fiber on constipation: A meta analysis. [online] ResearchGate. Available at: https://www.researchgate.net/publication/234158683_Effect_of_dietary_fiber_on_constipation_A_meta_analysis#:~:text=.%2C%202012).-,In%20a%20meta%2Danalysis%20by%20Yang%20et%20al.,their%20bowel%20movements.%20…
- Mari, A., Fadi Abu Backer, Mahmud Mahamid, Amara, H., Carter, D., Boltin, D. and Dickman, R. (2019). Bloating and Abdominal Distension: Clinical Approach and Management. [online] 36(5), pp.1075–1084. doi:https://doi.org/10.1007/s12325-019-00924-7.
- Wang, X., Zhang, P. and Zhang, X. (2021). Probiotics Regulate Gut Microbiota: An Effective Method to Improve Immunity. [online] 26(19), pp.6076–6076. doi:https://doi.org/10.3390/molecules26196076.
- Cristofori, F., Dargenio, V.N., Dargenio, C., Miniello, V.L., Barone, M. and Francavilla, R. (2021). Anti-Inflammatory and Immunomodulatory Effects of Probiotics in Gut Inflammation: A Door to the Body. Frontiers in Immunology, [online] 12. doi:https://doi.org/10.3389/fimmu.2021.578386.