Department of Epidemiology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy.
Mol Nutr Food Res. 2014 Sep;58(9):1907-14. doi: 10.1002/mnfr.201400169. Epub 2014 Jun 27.
To provide updated quantitative estimates of the associations between allium vegetables intake and risk of colorectal cancer and colorectal adenomatous polyps.
We combined all published data on the issue, using a meta-analytic approach. Pooled relative risks (RRs) were calculated using random-effects models. Sixteen studies (13 333 cases) were included in the meta-analyses of colorectal cancer. Seven studies provided information on garlic, six on onion, and four on total allium vegetables. The pooled RRs of colorectal cancer for the highest versus the lowest category of intake were 0.85 (95% confidence interval; CI, 0.72-1.00) for garlic (0.76 for case-control, 0.99 for cohort studies), 0.85 (95% CI, 0.70-1.04) for onion (0.74 for case-control, 1.04 for cohort studies), and 0.78 (95% CI, 0.56-1.08) for total allium vegetables. Significant heterogeneity was found for the three meta-analyses. The pooled RR of colorectal adenomatous polyps for the highest versus the lowest category of total allium vegetables intake was 0.88 (95% CI, 0.80-0.98, three studies), with no heterogeneity.
High garlic intake may reduce the risk of colorectal cancer. However, evidence of such protection derived mainly from case-control studies. High intake of total allium vegetables may be associated with a risk reduction of colorectal adenomatous polyps.
提供更新的定量估计，了解食用葱属蔬菜与结直肠癌和结直肠腺瘤性息肉风险之间的关联。
我们使用荟萃分析方法结合了所有关于该问题的已发表数据。使用随机效应模型计算汇总相对风险（RR）。共有 16 项研究（13333 例病例）纳入了结直肠癌的荟萃分析。有 7 项研究提供了大蒜的数据，6 项研究提供了洋葱的数据，4 项研究提供了总葱属蔬菜的数据。摄入最高与最低类别的葱属蔬菜与结直肠癌的汇总 RR 分别为大蒜 0.85（95%置信区间；CI，0.72-1.00）（病例对照研究为 0.76，队列研究为 0.99）、洋葱 0.85（95%CI，0.70-1.04）（病例对照研究为 0.74，队列研究为 1.04）和总葱属蔬菜 0.78（95%CI，0.56-1.08）。这三项荟萃分析均存在显著异质性。摄入总葱属蔬菜最高与最低类别与结直肠腺瘤性息肉的汇总 RR 为 0.88（95%CI，0.80-0.98，三项研究），无异质性。
高摄入量的大蒜可能降低结直肠癌的风险。然而，这种保护作用的证据主要来自病例对照研究。高摄入量的总葱属蔬菜可能与结直肠腺瘤性息肉风险降低相关。
