Bowel cancer is the fourth most common cancer affecting people in Australia. In positive news 99% of cases can be treated effectively when detected in the earliest stage. Unfortunately, fewer than 50% of cases are detected early.

In this article we look at factors that can increase the risk of bowel cancer, and what you can do to reduce your risk.

Seven risk factors you can change:

• Your level of physical activity
• Your weight and waist circumference
• Smoking
• Heavy alcohol use
• Red meat consumption
• Fibre consumption
• Calcium consumption

Six risk factors you can’t change:

• Your age (being 50 years or older)
• Having type 2 diabetes
• Your ethnic background
• A personal or family (a first degree relative) history of bowel polyps or bowel cancer
• Having an inflammatory bowel disease, for example ulcerative colitis or Crohn’s disease
• Having an inherited syndrome like Lynch syndrome, Peutz-Jeghers syndrome, or MYH-associated polyposis

How can you reduce your chances of developing bowel cancer?

1. Be physically active

Physical activity helps your food pass through the bowel faster to reduce the time potential carcinogens in the food are in contact with the bowel wall, it also helps to achieve a healthy weight and reduces insulin resistance. Thirty to 60 minutes of exercise a day is recommended.

2. Watch your weight

Being a healthy weight for your age, height, and ethnicity along with having a healthy waist circumference can reduce your risk too. Higher levels of body fat are associated with elevated insulin levels and chronic inflammation, which can stimulate cell growth and contribute to processes that increase the risk of bowel cancer. Your GP, diabetes educator, dietitian, and exercise physiologist can work out what weight and waistline is ideal for you. Your dietitian can help you make small changes to your eating to reduce your weight.

3. Stop smoking

The longer you smoke, the more you increase your risk of getting bowel cancer. Your GP can assess your nicotine dependence, discuss medications eg patches, gums, and explore your barriers to quitting. Or give Quitline a call on 137848.

4. Alcohol

Cut out alcohol entirely or reduce your daily alcohol use—the more you drink the greater your risk.

5. Limit red meat

Avoid large amounts of red meat. The World Cancer Research Fund recommends limiting consumption to no more than about three portions per week. The equivalent of between 350–500g cooked weight. It is also recommended to consume very little, if any, processed meat.

6. Add more fibre

Eat foods high in dietary fibre every day, including wholegrains, fruit, vegetables and legumes as the fibre, vitamins, bioactive compounds and antioxidants are protective for the bowel.

7. Keep up the calcium

Eat foods containing calcium such as dairy products or supplements. Check with your doctor before taking calcium supplements.

Bowel cancer symptom checker

If you have one of these symptoms for more than two weeks than you should see your GP:

• Blood in the stool or rectal bleeding
• Abdominal pain or swelling
• A change in bowel habits that is recent and persistent
• Pain or a lump in the anus or rectum
• Unexplained anaemia (low red blood cell count)
• A feeling that the bowel has not emptied completely after a bowel motion.

When should you start tests to diagnose bowel cancer?

Some people don’t get any signs or symptoms of bowel cancer which is why screening tests have been developed. You should start bowel cancer screening tests:

1. If you are 50 years of age
2. If you are 45 years of age with a relative with bowel cancer at 55 years or older

Talk with your GP as to how often you should have a screening test done as risk factors are considered. A faecal immunochemical test (FIT) is recommended for those with type 2 diabetes every one to two years. Call the Bowel Cancer Australia helpline on 1800 727 336 for more information on how to order this FIT test if you do not receive one in the mail once you turn 50.

This article was originally published on 4 May 2022