Alcohol, weight and education linked to early onset bowel cancer – new evidence

A new study published this week in Annals of Oncology has shed light on the possible reasons for the rise in bowel cancer in people under 50 years old.

7 March 2024

World Cancer Research Fund part-funded the study authored by the International Agency for Research on Cancer (IARC) which has found connections between early-onset bowel (also known as colorectal) cancer and various genetic and socio-economic factors. They found strong links with body fat, alcohol consumption, and educational attainment.

This genome-wide association study, the first of its kind, looked at more than 70,000 people, including almost 6,200 people under 50 who had been diagnosed with bowel cancer. Rates of early-onset bowel cancer are on the increase in many parts of the world, but the reasons are not yet fully understood.

The researchers identified new genetic variants associated with the development of early-onset bowel cancer, as well as confirming known pathways involved in bowel cancer development.

The team used Mendelian randomisation, which is a statistical way of analysing genetic variation between people. It analyses risk factors both independently and together, to help disentangle the direction of causality.

Dr Panagiota Mitrou, Director of Research, Policy and Innovation at World Cancer Research Fund, said:

This important study provides new insights into people’s genetic susceptibility to early-onset bowel cancer, as well as strengthening our knowledge of the modifiable risk factors involved, notably body weight and alcohol intake. It also shows the importance of socio-economic factors and health inequalities when it comes to early onset cancer prevention.

Dr Neil Murphy of the International Agency for Research on Cancer, who co-led the study, said:

Our study presents evidence showing the genes and environmental factors that are driving early-onset bowel cancer. It’s shown us that obesity and alcohol consumption may be important contributors to the rising rates of the disease. Public health efforts to address these important risk factors could lower the risk of early onset colorectal cancer for many people.

World Cancer Research Fund is funding research into many aspects of bowel cancer, for both prevention and survival, including the associations highlighted in this study. We are funding another study by Dr Murphy on bowel cancer in younger adults, as we work towards a world where no one dies of a preventable cancer.

> Read the paper in Annals of Oncology
> More about Dr Murphy’s research for World Cancer Research Fund