The study focused on aggressive prostate cancer, defined as cancers with a high grade or which resulted in death.
For every 4-inch increase in waist size, there was a 13% increase in having high grade prostate cancer. The risk of fatal prostate cancer increased by 18% for every 4-inch increase in waist circumference.
Increases in BMI were also associated with increased risks. For every 5 kg/m2 increase in BMI, there was a 10% increase in in having high grade prostate cancer and a 14% increase in having fatal prostate cancer.
Earlier studies have examined the link between body size, obesity and prostate cancer risk with mixed results. However, the authors concluded, "Our results are in line with health advice for other non- communicable diseases. Men should try to maintain a healthy weight." The Oxford study included over 140,000 men from eight European countries. After an average follow-up of 14 years, there were 7,022 cases of prostate cancer, 934 of which were fatal.
The findings were presented during the European Obesity Summit, which took place June 1-4, 2016 in Gothenburg, Sweden. The study has not yet been published or submitted to a medical journal.