Bowel cancer, also known as colorectal cancer, is a major health concern in the UK, with rising case numbers among young people year on year. As Dr Andrew Poullis, Consultant Gastroenterologist and Colonoscopist at New Victoria Hospital, explains, understanding your personal risk and making informed lifestyle choices can make a significant difference when it comes to prevention, early detection, and treatment.

Why Bowel Cancer Awareness Matters

Bowel cancer remains the fourth most common cancer and the second leading cause of cancer death in the UK. Around 45% of cases are thought to be preventable, meaning there is a lot that individuals can do to protect their health. Encouragingly, rates among people over 50 have been decreasing thanks to national screening programmes, which enable early detection and successful treatment. However, with rising numbers of cases among patients below 50, being proactive about bowel health isn’t just a seasonal concern for campaigns such as Decembeard – it’s vital all year round.

What Is Bowel Cancer?

Bowel cancer, also known as colorectal cancer, develops in the large bowel (colon) or the back passage (rectum). There are also other cancers that can affect the gastrointestinal (GI) tract and accessory organs and are named according to their location, including the oesophagus, stomach, small intestine, liver, pancreas, and gallbladder cancers.

Who Is at Risk?

Several factors can increase your risk of developing bowel cancer. These include being over the age of 50, having a family history of the disease or certain genetic conditions. Lifestyle factors also play a role, such as a diet high in red and processed meats and low in fibre or calcium, being overweight or obese, physical inactivity, excess alcohol consumption, and smoking. Medical conditions can contribute too, including long-standing inflammatory bowel disease (IBD), type 2 diabetes, or a previous history of bowel cancer or polyps.

Dietary Factors

• High intake of red and processed meat increases risk; processed meats include bacon, ham, sausages. Linked to ~13% of UK cases.
• Low fibre intake is strongly associated with higher risk; ~28% of UK cases. Wholegrains, fruits, and vegetables help reduce risk.
• Low calcium intake. Higher calcium (e.g., dairy or fortified plant milk) may lower risk; evidence is still emerging.

Lifestyle Factors

• Being overweight or obese accounts for ~11% of UK cases; higher BMI significantly raises risk.
• Physical inactivity. Regular activity helps maintain healthy weight and may independently lower risk.
• Smoking tobacco is linked to ~7% of UK cases; risk rises with number of cigarettes smoked.
• Alcohol consumption is associated with ~6% of UK cases; risk increases with amount consumed.

Age

• Older age. It can affect adults of any age, but while the proportion of younger patients is growing, it is most common after the age of 50. Most cases occur in people aged 75+, with over 43% of UK cases.
• However, early-onset cases (25–49 y.o.) are increasing, with England and Wales among the countries with the biggest rise in the proportion of cases in this age group: from 6.4% in 2021 to 8.0% in 2023.

Family History & Genetics

• Close relatives with bowel cancer. Risk increases with first-degree relatives, especially if diagnosed young or multiple cases.
• Inherited syndromes. Rare, inherited genetic conditions such as FAP and Lynch Syndrome greatly increase bowel cancer risk. Other rare syndromes include MUTYH- associated polyposis, Peutz-Jeghers, Juvenile Polyposis, and PTEN Hamartoma. Specialist advice and regular screening are recommended for people with these syndromes.

Medical Conditions

• Ulcerative colitis & Crohn’s disease. Long-term inflammation increases risk.
• Previous bowel cancer. Raises risk of another occurrence.
• Type 2 diabetes. Associated with higher risk; cause unclear.
• Acromegaly. A rare condition, when pituary gland makes too much growth hormone (GH), has been linked to increased risk of cancers, including colorectal; mechanism under study.

Other Biological Factors

• Benign polyps (adenomas). Common; some can develop into cancer over the years.
• Ionising radiation exposure. A very small link to bowel cancer risk; includes radiotherapy, some diagnostic scans, and environmental radon. However, the risk from imaging tests is minimal compared with the value of a correct diagnosis.

Recognising Symptoms Early 

Early diagnosis significantly improves survival rates. Watch for these symptoms and seek medical advice if they persist: 

• Change in bowel habit (looser stools, or needing to go more often) 

• Blood in the stools or bleeding from the bottom 

• Unexplained abdominal pain, discomfort, or bloating (especially after eating) 

• Unintentional weight loss 

• Feeling tired or breathless due to anaemia 

Not all symptoms mean cancer, but prompt investigation can ensure other causes are found or that signs of cancer are caught early. 

It is also important to note that most precancerous polyps do not have symptoms, and they are often found during a colonoscopy. For those in higher-risk groups, proactive measures like regular screening and specialist advice can help detect and remove polyps before they become a concern.

Why Is Early-Onset Colorectal Cancer on the Rise?

Causes for the increasing incidence of bowel cancer among young adults under 50 are unclear. Many studies are currently investigating the impact that ultra-processed foods (UPFs) and lifestyle have had. Different studies are now suggesting that there is an association between UPFs and polyp growth. 

One 2022 BMJ study observed that men who consumed the highest quantity of UPFs had a 29% increased risk of developing colorectal cancer, with a positive association for distal (left side) colon cancer, but no association was found for women consuming UPFs. However, a positive correlation was found for women consuming ready-to-eat meals. Whereas yoghurt and dairy desserts were associated with a reduced risk of bowel cancer, likely due to their calcium content, which may offer a protective effect. 

The Nurses’ Health Study and Health Professionals Follow-up Study followed 29,100 American women, mostly Caucasian, aged 25-42, for a period of 24 years. Women who consumed about 10 servings of UPFs per day had a 45% increased risk of developing adenomas than those who consumed the least (3.3 servings per day). Colonoscopies performed before the age of 50 showed that 1 in 25 women had developed polyps in their bowel.

“Research so far has not proved a direct causation link between ultra-processed foods and bowel cancer. More studies are needed among a diverse population to understand the mechanisms behind the association. However, a more plant-based diet with at least 30g of fibre per day that also includes a diverse combination of plants is key in maintaining a healthy gut microbiome, which strengthens the immune system and reduces cancer risk”, Dr Andrew Poullis, BSc, MBBS, MD, PGCert HBE, FRCP, Consultant Gastroenterologist at New Victoria Hospital 

Bowel Cancer Prevention: Evidence-Based Advice

There is robust scientific evidence for several lifestyle changes that can help reduce your risk of bowel cancer: 

1. Eat More Fibre and Whole Plant Foods. A diet rich in fibre from vegetables, whole grains, pulses, and fruit helps keep your digestive tract healthy and may lower cancer risk. Swapping white bread or rice for wholegrain versions and aiming for ‘five a day’ fruit and vegetables are simple, effective changes.  

2. Limit Ultra-Processed Food, Red and Processed Meat. Cutting back on red meats (beef, lamb, pork) and processed meats (bacon, sausage, ham) is strongly recommended. Research supports choosing leaner poultry, fish, and plant-based proteins more often. 

3. Keep a Healthy Weight. Being overweight, especially around the waist, is a recognised risk factor for bowel cancer. Weight management, through diet and exercise, is important for overall health and can help lower risk.​ 

4. Be Physically Active. Aim for at least 150 minutes of moderate activity each week – both walking and cycling count. Even small increases in daily movement can have positive effects. 

5. Limit Alcohol Intake. Guidelines suggest ot regularly exceeding 14 units of alcohol per week and spreading this amount over several days. Less is better, and alcohol-free days each week are helpful.  

6. Stop Smoking. Smoking increases your risk of many cancers, including bowel cancer. Quitting is one of the most effective steps for cancer prevention. 

7. Ensure Adequate Calcium and Vitamin D. Some research suggests calcium-rich foods (like low-fat dairy) and maintaining good vitamin D levels could be helpful for bowel health, although this should be part of an overall balanced diet.​ 

8. Don’t Ignore Screening Invitations. Take part in the NHS Bowel Cancer Screening Programme when invited to. Even in the absence of symptoms, regular screening helps catch cancers early. Testing from age 50 or earlier if at high risk, as recommended by your doctor, is essential for early detection and better outcomes.

Learn more about our services on our Bowel Cancer and Gastroenterology pages.

Frequently Asked Questions 

Q: Can young people get bowel cancer? 

A: While it’s most common in older adults, bowel cancer can affect younger adults too, especially those with a strong family history or longstanding inflammatory bowel disease. Raising awareness among all ages supports earlier detection. ​ 

Q: What if I don’t have any symptoms? 

A: Screening catches early, symptomless cancers. Free FIT test within the NHS screening programme is offered to patients over 65; however, if you have a family history of bowel cancer or other risk factors, you should speak to your GP. You can also book an appointment with a Consultant Gastroenterologist to discuss your concerns and consider proactive screening, especially if you are over 40 years of age. 

Q: Is a colonoscopy painful? 

A: Colonoscopy is usually well-tolerated. Sedation and supportive care make it as comfortable as possible, with your consultant explaining what to expect and answering questions throughout the process. New Victoria Hospital has been awarded JAG accreditation by the Royal College of Physicians, offering our patients full confidence in the high-quality and safety standards of our Endoscopy services. 

Take the Next Step for Your Bowel Health 

If you are experiencing any bothersome symptoms or changes in your bowel habits, would like peace of mind, or know you are at higher risk, our Consultants can advise on the most appropriate checks and preventative care for you. Early action ensures the best possible outcomes. 

To book a private appointment with our Gastroenterology Consultants at New Victoria Hospital, please call 020 8949 9020 or fill in our online contact form. 

This article is for general information only and does not replace individual medical advice. Please consult a healthcare professional for personalised recommendations.