Effects of physical condition and body composition on cancer risk in a nationwide cohort of 31,158 men from Finland.

Abstract

1565 Background: Regular physical activity seems to protect men from colorectal cancer and possibly also from prostate cancer. In the case of other cancers the evidence is adding up, and physical activity seems to have a small protective effect to its incidence. The aim of this study was to analyse the effects of physical condition (PC) in early adulthood on cancer incidence later in life. Methods: We collected data on general health, anthropometry and PC for 31,158 Finnish men born in 1958 from the time of their military service between the ages of 17 and 30 years. Using linkage with the Finnish Cancer Registry, all men were followed-up for cancer incidence up to 2014. Results: Overweight and obesity (body mass index (BMI) ≥ 25 kg/m2) were associated with an increased overall cancer risk [hazard ratio (HR): 1.08, 95% confidence interval (CI): 0.89-1.30] when compared to those with BMI < 25 kg/m2. Those with normal weight but bad PC had an increased risk of all cancers combined as compared to those with normal weight and good PC (HR 1.18, 95% CI: 1.01-1.38), which further increased in those who were also overweight (HR 1.30, 95% CI: 1.01-1.69). We noticed an increased overall cancer risk in men in who entered service with minor health problems (HR 1.46, 95% CI 1.19-1.80), when compared to those that were completely healthy. This was especially observed for advanced prostate cancer (HR: 3.35, 95% CI: 1.14-9.90). Increased HRs, yet statistically insignificant, were also seen for colorectal and other obesity-related cancers. Conclusions: Good PC at young age seems to protect men from cancer later in life. Early adulthood obesity, when combined with bad PC, seems to further increase cancer risk.