Leisure-time Activities and Obesity-related Cancers

A new study published in the International Journal of Cancer suggests that leisure-time activities minimize the incidence of obesity-related cancers. Physical activity (PA) was lower in both normal weight and overweight people, and it was even lower when physical activity and normal weight were combined.

The increased incidence of overweight/obesity among children and adolescents in modern culture is thought to be due to inactivity or low levels of physical activity mixed with changes in eating habits. Although physical activity has been linked to a decreased risk of obesity-related malignancies, the combined effect of physical activity and body weight on obesity-related cancer risk is less apparent. In five Scandinavian cohorts, we looked at the impact of leisure-time PA (high/low) and its combination with BMI on obesity-related cancer risk in 570,021 people, who were on average 43 years old at the start.

The hazard ratios of obesity-related malignancies (n = 19,074) were calculated using Cox regression, and multiplicative and cumulative interactions between PA and BMI on risk were evaluated.

Key Findings

• When compared to low PA, high leisure-time PA was linked with a 7% reduced risk of any obesity-related malignancy, with comparable relationships across those with a low and a high BMI.
• High PA was also linked to a lower incidence of renal cell cancer and colon cancer.
• In comparison to low PA-high BMI, the relative risk reduction for all obesity-related cancers was 24%; endometrial cancer, 47%; renal cell cancer, 39%; colon cancer, 27%; multiple myeloma, 23%; and pancreatic cancer, 21%.
• The effects of PA and BMI on risk were neither additive nor multiplicative.

In conclusion, in both normal weight and overweight people, moderate to vigorous leisure-time physical exercise may reduce the incidence of all obesity-related malignancies when compared to mild or no activity.

Reference

Sun, M., Bjørge, T., Teleka, S., Engeland, A., Wennberg, P., Häggström, C., & Stocks, T. (2022). Interaction of leisure‐time physical activity with body mass index on the risk of obesity‐related cancers: A pooled study. In International Journal of Cancer. Wiley. https://doi.org/10.1002/ijc.34011