Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
Am J Clin Nutr. 2012 Jan;95(1):147-54. doi: 10.3945/ajcn.111.020479. Epub 2011 Dec 14.
Isoflavones are structurally similar to 17β-estradiol and may be able to prevent gastric cancer. However, there is contradictory evidence concerning the relation between the intake of soy food, which is rich in isoflavones, and gastric cancer. The association with gastric cancer might differ between isoflavones and soy foods, and research on the effects of isoflavone intake alone on gastric cancer is needed.
We investigated the association between isoflavone intake and the incidence of gastric cancer.
We conducted a large, population-based prospective study of 39,569 men and 45,312 women aged 45-74 y. Dietary soy and isoflavone intakes were measured by using a validated food-frequency questionnaire in 1995 and 1998.
During 806,550 person-years of follow-up, we identified 1249 new gastric cancer cases. Isoflavone intake was not associated with gastric cancer in either men or women. Compared with the lowest quartile, the HR and 95% CI for developing gastric cancer in the fourth quartile of isoflavone intake was 1.00 (0.81, 1.24) for men and 1.07 (0.77, 1.50) for women. In a stratified analysis by exogenous female hormones (women only), however, we found an increasing trend in risk of gastric cancer associated with higher isoflavone intakes among exogenous female hormone users (P-trend = 0.03) but not for nonusers (P-interaction = 0.04).
The current study does not support the hypothesis that higher intakes of isoflavones prevent gastric cancer in either men or women.
异黄酮的结构与 17β-雌二醇相似，可能具有预防胃癌的作用。然而，关于富含异黄酮的大豆食品摄入量与胃癌之间的关系，目前的证据相互矛盾。异黄酮和大豆食品与胃癌的相关性可能存在差异，需要研究单独摄入异黄酮对胃癌的影响。
我们调查了异黄酮摄入量与胃癌发病风险之间的关系。
我们对 39569 名男性和 45312 名年龄在 45-74 岁的女性进行了一项大型的基于人群的前瞻性研究。1995 年和 1998 年通过验证后的食物频率问卷来评估膳食中大豆和异黄酮的摄入量。
在 806550 人年的随访期间，我们共发现 1249 例新发胃癌病例。异黄酮摄入量与男性或女性的胃癌均无相关性。与最低四分位数相比，异黄酮摄入量最高四分位数者发生胃癌的 HR（95%CI）为男性 1.00（0.81，1.24），女性 1.07（0.77，1.50）。然而，在按外源性雌激素（仅女性）分层的分析中，我们发现外源性雌激素使用者中，胃癌风险与异黄酮摄入量的增加呈正相关趋势（P 趋势=0.03），而非使用者则无此趋势（P 交互=0.04）。
本研究结果不支持异黄酮摄入量较高可预防男性或女性胃癌的假说。
