Why do people get polyps? A Comprehensive Look at Causes and Risk Factors

September 21, 2025 •

4 min read

Affecting up to 40% of adults aged 45 and older, polyps are abnormal cell growths that can appear in various parts of the body. The reasons why do people get polyps can be complex, often stemming from a mix of genetic predispositions and environmental influences. This guide explores the underlying causes and key risk factors associated with polyp formation.

Quick Summary

Polyps develop due to uncontrolled cell growth triggered by factors like chronic inflammation, inherited genetic mutations, and lifestyle choices. They are often benign but can become cancerous over time, making early detection and removal crucial for managing risk and preventing complications, especially in the colon.

Key Points

Genetic Factors: Inherited syndromes like FAP and Lynch syndrome can significantly increase your risk of developing numerous polyps, especially in the colon.
Inflammation is a Trigger: Chronic irritation from inflammatory conditions or environmental factors, such as allergens or toxins, can lead to abnormal cell growth and polyp formation.
Lifestyle Plays a Major Role: Diet high in red/processed meats and low in fiber, along with smoking, excess alcohol, and obesity, can increase polyp risk.
Not All Polyps are Equal: The risk of a polyp becoming cancerous depends on its type (e.g., adenomatous vs. hyperplastic), size, and location.
Early Detection is Crucial: Since many polyps are asymptomatic, regular health screenings like a colonoscopy are vital for detecting and removing them before they can turn cancerous.
Location Matters: The specific causes of polyps can differ depending on where they form in the body, such as the colon, sinuses, or uterus.

Understanding the Origins of Polyp Formation

Polyps are tissue growths that form on mucous membranes, the moist linings of hollow organs, throughout the body. While most are non-cancerous, some can become malignant over time, which is why understanding their cause is so important. The development of a polyp is often a multi-stage process involving abnormal cell division and an accumulation of cellular mutations.

Genetic Influences on Polyp Development

Genetics play a significant role in determining a person's risk of developing polyps. Certain inherited syndromes directly lead to the growth of multiple polyps and significantly increase the risk of cancer.

Familial Adenomatous Polyposis (FAP): A rare disorder caused by a mutation in the APC gene. Individuals with FAP can develop hundreds to thousands of polyps in their colon, with a nearly 100% risk of developing colorectal cancer if left untreated.
Lynch Syndrome: Also known as Hereditary Non-Polyposis Colorectal Cancer (HNPCC), this syndrome involves gene mutations that cause polyps to develop at a younger age and progress to cancer more quickly.
MUTYH-Associated Polyposis (MAP): Caused by mutations in the MUTYH gene, this condition can lead to multiple adenomatous polyps and a high risk of colon cancer.
Peutz-Jeghers Syndrome: An inherited condition characterized by hamartomatous polyps throughout the gastrointestinal tract and increased risk of several cancers. It is also marked by characteristic small, dark freckles around the mouth and on other body parts.

Environmental and Lifestyle Risk Factors

Even without a genetic predisposition, various environmental and lifestyle factors can contribute to the formation of polyps, particularly colorectal polyps. These factors often trigger chronic irritation and inflammation in the affected area.

Age: The risk of developing polyps increases with age, with most cases occurring in people over 45.
Chronic Inflammation: Conditions that cause long-term inflammation, such as ulcerative colitis and Crohn's disease, can increase the risk of developing inflammatory polyps. This constant cellular irritation can lead to abnormal tissue growth.
Diet: A diet high in red and processed meats and low in fiber is linked to an increased risk of colon polyps. Conversely, a diet rich in fruits, vegetables, and whole grains is associated with lower risk.
Obesity and Sedentary Lifestyle: Being overweight and a lack of regular physical activity are significant risk factors for polyp formation.
Tobacco and Alcohol Use: Both smoking and excessive alcohol consumption are known to increase the risk of polyps in the colon and other areas.

Other Specific Causes by Location

Polyps can occur in different parts of the body, and the specific causes can vary based on their location.

Nasal Polyps: Often linked to chronic sinus inflammation, allergies, asthma, and sensitivities to substances like aspirin.
Uterine Polyps: Thought to be influenced by hormonal factors, particularly excess estrogen, and are more common after menopause.
Stomach Polyps: Can be associated with chronic gastritis caused by H. pylori bacteria or the long-term use of certain acid-reducing medications.
Gallbladder Polyps: While their cause is less clear, they are sometimes linked to gallstones, chronic inflammation, or high cholesterol.

Comparing Types of Colorectal Polyps

Understanding the specific type of polyp is crucial for determining the potential risk of it becoming cancerous. Polyps are typically classified as neoplastic (precancerous) or non-neoplastic (not precancerous).


Type of Polyp	Characteristics	Cancer Risk
Adenomatous Polyps	Most common type; includes tubular, villous, and tubulovillous subtypes.	Precancerous; risk increases with size and villous components.
Serrated Polyps	Can be sessile or traditional. Often flat and hard to detect.	Precancerous; sessile serrated polyps have a significant cancer risk.
Hyperplastic Polyps	Small, typically located in the lower colon.	Non-precancerous; generally considered harmless.
Inflammatory Polyps	Occur in individuals with inflammatory bowel diseases (IBD).	Non-precancerous; while not malignant themselves, they are markers of chronic inflammation that can increase overall cancer risk.

The Importance of Screening and Prevention

Given that many polyps, especially precancerous ones, produce no symptoms, regular screenings are critical for early detection and removal. A colonoscopy is the gold standard for detecting and removing colon polyps in the same procedure, effectively stopping their progression to cancer. For individuals with a family history or genetic syndromes, earlier and more frequent screenings are recommended.

Making healthy lifestyle choices, such as maintaining a healthy weight, exercising regularly, and adopting a high-fiber, low-fat diet, can also help reduce the risk of polyp formation. Avoiding tobacco and limiting alcohol are further preventive measures that can significantly improve overall health. Consult with a healthcare provider to determine the most appropriate screening schedule and preventive strategies for your individual health profile.

Conclusion

Polyp formation is a complex process influenced by a mix of genetic, environmental, and lifestyle factors. While most polyps are benign, certain types carry a risk of developing into cancer over time. Early detection through regular screenings and adopting a healthy lifestyle are the most effective ways to manage this risk. Understanding the causes and risk factors empowers individuals to take proactive steps toward protecting their health and preventing serious complications down the line. Remember, a healthcare professional can provide personalized guidance and a screening schedule tailored to your specific needs.

Learn more about hereditary polyposis syndromes and their genetic basis on this authoritative page.

Frequently Asked Questions

The primary cause of polyps is abnormal cell growth, often triggered by a combination of genetic factors, which involve faulty genes, and environmental or lifestyle factors, such as chronic inflammation, a high-fat diet, and smoking.

No, not all polyps are precancerous. There are several types, including non-neoplastic polyps (like hyperplastic polyps) that are generally benign, and neoplastic polyps (like adenomas) that have the potential to become cancerous over time.

Yes, diet can significantly influence your risk. Diets high in red and processed meats and low in fiber are linked to a higher risk of colon polyps. A diet rich in fruits, vegetables, and whole grains is recommended for prevention.

You should be concerned about polyps if you have risk factors such as a family history, or if you experience symptoms like blood in your stool, changes in bowel habits, or abdominal pain. Regular screenings are key for everyone, especially those over 45.

Most polyps found during a colonoscopy or endoscopy can be removed at the same time using specialized instruments. The removed tissue is then sent for biopsy to determine if it is cancerous.

While it is possible for new polyps to form, complete removal makes it unlikely for the same polyp to grow back. However, individuals who have had polyps before have a higher risk of developing new ones, which is why continued surveillance is necessary.

Common risk factors include increasing age (over 45), a family history of polyps or cancer, genetic syndromes (like FAP), chronic inflammation (IBD), obesity, and lifestyle habits such as smoking and excessive alcohol consumption.