Dietary carrot consumption and the risk of prostate cancer
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Previous studies regarding the association between carrot intake and prostate cancer risk have reported inconsistent results. We conducted a meta-analysis to summarize evidence on this association and to quantify the potential dose–response relationship.
A systematic literature search of papers published in August 2013 was conducted using PubMed, EMBASE, Scopus, Web of Science, the Cochrane register, and the Chinese National Knowledge Infrastructure databases, and the references of the retrieved articles were screened. The summary risk estimates with 95 % confidence intervals (CIs) for the highest versus the lowest intake of carrots were calculated. A dose–response meta-analysis was also conducted for the studies reporting categorical risk estimates for a series of exposure levels.
We found a significantly decreased risk of prostate cancer associated with the intake of carrots (odds ratio 0.82, 95 % CI 0.70–0.97). In addition, the dose–response meta-analysis indicated that for each serving per week, or 10 g per day increment of carrot intake, the risk estimate of prostate cancer was 0.95 (0.90–0.99) or 0.96 (0.94–0.99). There was no evidence of significant publication bias based on Begg’s funnel plot (P = 1.000) or Egger’s test (P = 0.804).
Carrot intake might be inversely associated with prostate cancer risk. Because of the limited number of cohort studies and substantial heterogeneity observed between studies in this meta-analysis, further well-designed prospective studies are warranted to confirm the findings from our study.
KeywordsCarrot Prostatic neoplasms Meta-analysis Epidemiology
This study was supported by grants from the National Key Clinical Specialty Construction Project of China, key medical disciplines of Zhejiang Province, combination of traditional Chinese and Western medicine key disciplines of Zhejiang Province (2012-XK-A23), health sector scientific research special project (201002010), National Natural Science Foundation of China (Grant No. 81101717), and Zhejiang Provincial Natural Science Foundation of China (Grant No. Y2110120).
Conflict of interest
The authors declare no conflict of interest.
- 10.Kolonel LN, Hankin JH, Whittemore AS, Wu AH, Gallagher RP, Wilkens LR, John EM, Howe GR, Dreon DM, West DW, Paffenbarger RS Jr (2000) Vegetables, fruits, legumes and prostate cancer: a multiethnic case–control study. Cancer Epidemiol Biomarkers Prev 9:795–804Google Scholar
- 20.Mantel N, Haenszel W (1959) Statistical aspects of the analysis of data from retrospective studies of disease. J Natl Cancer Inst 22:719–748Google Scholar
- 23.Greenland S, Longnecker MP (1992) Methods for trend estimation from summarized dose–response data, with applications to meta-analysis. Am J Epidemiol 135:1301–1309Google Scholar
- 33.Frei B (1994) Reactive oxygen species and antioxidant vitamins: mechanisms of action. Am J Med 97:5S–13S (discussion 22S–28S)Google Scholar
- 38.Zeegers MP, Goldbohm RA, van den Brandt PA (2001) Consumption of vegetables and fruits and urothelial cancer incidence: a prospective study. Cancer Epidemiol Biomarkers Prev 10:1121–1128Google Scholar