A healthier lifestyle after bowel screening shown to prevent bowel cancer

By Admin

03 Oct, 2025

Bowel cancer is one of the most common cancers worldwide, with Norway ranking among the countries with the highest incidence. However, a new study has revealed that making positive lifestyle changes after bowel cancer screening can significantly reduce the risk of not only bowel cancer but also other chronic diseases.

Lifestyle Changes After Screening Make a Difference

Traditionally, research has shown that avoiding smoking, maintaining a healthy body weight, eating a balanced diet, exercising regularly, and limiting alcohol could prevent nearly half of all bowel cancer cases. However, most of these studies looked at lifetime habits. The new study takes a different angle: what happens if you improve your lifestyle after you’ve already been screened?

According to Markus Dines Knudsen, postdoctoral fellow at the Department of Nutrition, Institute of Basic Medical Sciences, and his collaborators at Harvard T.H. Chan School of Public Health, bowel screening may serve as a “teachable moment.” It can be a point in time when individuals are more open to making changes that improve their health outcomes.

What the Study Found

Published in the American Journal of Gastroenterology, the study examined data from three large U.S. studies involving people who had undergone colonoscopy. Participants answered questions about their diet and lifestyle before screening and then again at various points in the years following it.

Researchers developed a lifestyle score between 1 and 5, measuring smoking, body mass index, exercise, alcohol consumption, and diet (including intake of red/processed meat, fiber, whole grains, dairy, and calcium).

The findings were striking:

• For every one-point improvement in lifestyle score, the risk of bowel cancer dropped by 14%, while the risk of other chronic diseases fell by 11%.
  
  

• Improvements could include becoming more physically active, losing weight, or drinking less alcohol.
  
  

• Conversely, participants whose lifestyle worsened by two points or more faced a 70% higher risk of bowel cancer and a 21% higher risk of chronic diseases compared to those whose lifestyle remained stable.
  
  

“These are interesting results since we are dealing with a group who actually had a reduced risk of bowel cancer because they were screened for bowel cancer and pre-cancerous conditions,” Knudsen explained. “In spite of this, we found that when their lifestyle worsened, they had a pronounced increase in risk of getting bowel cancer.”

Next Steps: Norwegian Study in Progress

Building on these findings, Norwegian researchers are now launching a new study in collaboration with the Norwegian Cancer Registry’s Bowel Screening Program. Over a two-year period, they will test varying levels of follow-up and support for cancer-preventive lifestyle changes. Long-term, they aim to assess the impact of these measures on cancer incidence and mortality.

Bowel Cancer and Screening in Norway

• Around 5,000 people are diagnosed with bowel cancer in Norway each year.
  
  

• The national screening program allows individuals aged 55 and above to test for blood in the stool every other year for 10 years.
  
  

• The main goal is to detect precancerous growths or cancer at an early, more treatable stage.
  
  

Takeaway: Screening Is Only the First Step

The study sends a powerful message: screening alone is not enough. It is what people do afterwards that can make a lasting difference. Choosing to quit smoking, eat more healthily, exercise, and cut back on alcohol after a screening can reduce the risk of bowel cancer and promote overall health.

By viewing bowel screening as a wake-up call and an opportunity to reset lifestyle habits, individuals can take control of their health and significantly lower their long-term risk of cancer and chronic diseases.