A large study looked at food and bowel cancer in 461,682 Americans. Bowel cancer affects the large bowel, a part of the body. People were aged 50 to 71 at the start. They answered questions about their food once. Researchers then followed their health for nearly 19 years. They found no overall link between eating more highly processed food and higher bowel cancer rates. These foods go through many steps in factories.
But different foods showed different links. People ate wholegrain foods and foods made from milk. More of these highly processed foods went with lower cancer rates. More meat from highly processed foods went with higher rates. Researchers also looked at replacing some highly processed food with less processed food. Their calculation linked a change of 10% by food weight with a 2% lower cancer rate.
Most people in the study were older and white. The results may not be the same for other groups. People reported their diets only at the start, so researchers could not follow later changes in their eating. The study cannot show that these foods caused or prevented cancer. The findings suggest looking at what foods contain, not just how factories make them.
