Diet, supplement use, and prostate cancer risk: results from the prostate cancer prevention trial.
The authors examined nutritional risk factors for prostate cancer among 9,559 participants in the Prostate Cancer Prevention Trial (United States and Canada, 1994-2003). The presence or absence of cancer was determined by prostate biopsy, which was recommended during the trial because of an elevated prostate-specific antigen level or an abnormal digital rectal examination and was offered to all men at the trial's end. Nutrient intake was assessed using a food frequency questionnaire and a structured supplement-use questionnaire. Cancer was detected in 1,703 men; 127 cancers were high-grade (Gleason score 8-10). There were no associations of any nutrient or supplement with prostate cancer risk overall. Risk of high-grade cancer was associated with high intake of polyunsaturated fats (quartile 4 vs. quartile 1: odds ratio = 2.41, 95% confidence interval (CI): 1.33, 4.38). Dietary calcium was positively associated with low-grade cancer but inversely associated with high-grade cancer (for quartile 4 vs. quartile 1, odds ratios were 1.27 (95% CI: 1.02, 1.57) and 0.43 (95% CI: 0.21, 0.89), respectively). Neither dietary nor supplemental intakes of nutrients often suggested for prostate cancer prevention, including lycopene, long-chain n-3 fatty acids, vitamin D, vitamin E, and selenium, were significantly associated with cancer risk. High intake of n-6 fatty acids, through their effects on inflammation and oxidative stress, may increase prostate cancer risk.
Kristal
Alan R
AR
Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024, USA. akristal@fhcrc.org
Arnold
Kathryn B
KB
Neuhouser
Marian L
ML
Goodman
Phyllis
P
Platz
Elizabeth A
EA
Albanes
Demetrius
D
Thompson
Ian M
IM
D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D004032:Diet / Q000706:statistics & numerical data*; D019587:Dietary Supplements; D051517:Digital Rectal Examination; D015444:Exercise; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000517:prevention & control; D012307:Risk Factors; D012959:Socioeconomic Factors
D017430:Prostate-Specific Antigen