Search

Background: Red and processed meat have been consistently associated with colorectal cancer risk, but evidence for other cancer sites and for poultry intake is limited. We therefore examined associations between total, red and processed meat and poultry intake and incidence for 20 common cancers.Methods: We analyzed data from 474 996 participants (54% women) in UK Biobank. Participants were aged 37-73 years and cancer-free at baseline (2006-10). Multivariable-adjusted Cox proportional hazards models were used to determine associations between baseline meat intake and cancer incidence. Trends in risk across the baseline categories were calculated, assigning re-measured intakes from a subsample.Results: During a mean follow-up of 6.9 years, 28 955 participants were diagnosed with malignant cancer. After correction for multiple testing, red and processed meat combined, and processed meat, were each positively associated with colorectal cancer risk [hazard ratio (HR) per 70 g/day higher intake of red and processed meat 1.32, 95% confidence interval 1.14-1.53; HR per 20 g/day higher intake of processed meat 1.18, 1.03-1.31] and red meat was associated with colon cancer risk (HR per 50 g/day higher intake of red meat 1.36, 1.13-1.64). Positive associations of red meat intake with colorectal and prostate cancer, processed meat intake with rectal cancer and poultry intake with cancers of the lymphatic and haematopoietic tissues did not survive multiple testing.Conclusions: Higher intake of red and processed meat was specifically associated with a higher risk of colorectal cancer; there was little evidence that meat intake was associated with risk of other cancers. [ABSTRACT FROM AUTHOR]

Background: Previous studies suggest a protective role of physical activity in breast cancer risk, largely based on self-reported activity. We aimed to clarify this association by examining breast cancer risk in relation to self-reported physical activity, informed by accelerometer-based measures in a large subset of participants.Methods: We analysed data from 47,456 premenopausal and 126,704 postmenopausal women in UK Biobank followed from 2006 to 2014. Physical activity was self-reported at baseline, and at resurvey in a subsample of 6443 participants. Accelerometer data, measured from 2013 to 2015, were available in 20,785 women. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated by using multivariable-adjusted Cox regression.Results: A total of 3189 cases were diagnosed during follow-up (mean = 5.7 years). Women in the top compared with the bottom quartile of self-reported physical activity had a reduced risk of both premenopausal (RR 0.75; 95% CI 0.60-0.93) and postmenopausal breast cancer (RR 0.87; 95% CI 0.78-0.98), after adjusting for adiposity. In analyses utilising physical activity values assigned from accelerometer measurements, an increase of 5 milli-gravity was associated with a 21% (RR 0.79; 95% CI 0.66-0.95) reduction in premenopausal and a 16% (RR 0.84; 95% CI 0.73-0.96) reduction in postmenopausal breast cancer risk.Conclusions: Greater physical activity is associated with a reduction in breast cancer risk, which appears to be independent of any association it may have on risk through its effects on adiposity. [ABSTRACT FROM AUTHOR]

Background: Prostate cancer is the most common cancer in British men but its aetiology is not well understood. We aimed to identify risk factors for prostate cancer in British males.Methods: We studied 219 335 men from the UK Biobank study who were free from cancer at baseline. Exposure data were collected at recruitment. Prostate cancer risk by the different exposures was estimated using multivariable-adjusted Cox proportional hazards models.Results: In all, 4575 incident cases of prostate cancer occurred during 5.6 years of follow-up. Prostate cancer risk was positively associated with the following: black ethnicity (hazard ratio black vs white=2.61, 95% confidence interval=2.10-3.24); having ever had a prostate-specific antigen test (1.31, 1.23-1.40); being diagnosed with an enlarged prostate (1.54, 1.38-1.71); and having a family history of prostate cancer (1.94, 1.77-2.13). Conversely, Asian ethnicity (Asian vs white hazard ratio=0.62, 0.47-0.83), excess adiposity (body mass index (⩾35 vs <25 kg m-2=0.75, 0.64-0.88) and body fat (⩾30.1 vs <20.5%=0.81, 0.73-0.89)), cigarette smoking (current vs never smokers=0.85, 0.77-0.95), having diabetes (0.70, 0.62-0.80), and never having had children (0.89, 0.81-0.97) or sexual intercourse (0.53, 0.33-0.84) were related to a lower risk.Conclusions: In this new large British prospective study, we identified associations with already-established, putative and possible novel risk factors for being diagnosed with prostate cancer. Future research will examine associations by tumour characteristics. [ABSTRACT FROM AUTHOR]