Keinan-Boker Lital, van Der Schouw Yvonne T, Grobbee Diederick E, Peeters Petra H M
Julius Center for Health Sciences and Primary Care, University Medical Center, Utrecht, Netherlands.
Am J Clin Nutr. 2004 Feb;79(2):282-8. doi: 10.1093/ajcn/79.2.282.
A high intake of phytoestrogens, particularly isoflavones, has been suggested to decrease breast cancer risk. Results from human studies are inconclusive.
We investigated the association between phytoestrogen intake and breast cancer risk in a large prospective study in a Dutch population with a habitually low phytoestrogen intake.
The study population consisted of 15 555 women aged 49-70 y who constituted a Dutch cohort of the European Prospective Investigation into Cancer and Nutriton (EPIC; 1993-1997). Data concerning habitual dietary intake in the preceding year were obtained by using a validated food-frequency questionnaire. The content of isoflavones and lignans in relevant food items was estimated through a literature search, the use of food-composition tables, and contact with experts. Newly diagnosed breast cancer cases up to 1 January 2001 were identified through linkage with the Comprehensive Cancer Center Middle Netherlands. Hazard ratios for the disease were estimated by Cox proportional hazard analysis for quartiles of isoflavone and lignan intake. Associations were adjusted for known breast cancer risk factors and daily energy intake.
A total of 280 women were newly diagnosed with breast cancer during follow-up. The median daily intakes of isoflavones and lignans were 0.4 (interquartile range: 0.3-0.5) and 0.7 (0.5-0.8) mg/d, respectively. Relative to the respective lowest intake quartiles, the hazard ratios for the highest intake quartiles for isoflavones and lignans were 1.0 (95% CI: 0.7, 1.5) and 0.7 (0.5, 1.1), respectively. Tests for trend were nonsignificant.
In Western populations, a high intake of isoflavones or mammalian lignans is not significantly related to breast cancer risk.
高摄入植物雌激素，尤其是异黄酮，被认为可降低乳腺癌风险。人体研究结果尚无定论。
在荷兰人群中进行一项大型前瞻性研究，该人群植物雌激素摄入量通常较低，我们调查了植物雌激素摄入量与乳腺癌风险之间的关联。
研究人群包括15555名年龄在49 - 70岁的女性，她们构成了欧洲癌症与营养前瞻性调查（EPIC；1993 - 1997年）的荷兰队列。通过使用经过验证的食物频率问卷获取前一年习惯性饮食摄入的数据。通过文献检索、使用食物成分表以及与专家联系，估算相关食物中异黄酮和木脂素的含量。通过与荷兰中部综合癌症中心的数据链接，确定截至2001年1月1日新诊断的乳腺癌病例。通过Cox比例风险分析估算异黄酮和木脂素摄入量四分位数的疾病风险比。对已知的乳腺癌风险因素和每日能量摄入进行了关联调整。
随访期间共有280名女性新诊断为乳腺癌。异黄酮和木脂素的每日摄入量中位数分别为0.4（四分位间距：0.3 - 0.5）和0.7（0.5 - 0.8）mg/d。相对于各自最低摄入四分位数，异黄酮和木脂素最高摄入四分位数的风险比分别为1.0（95% CI：0.7，1.5）和0.7（0.5，1.1）。趋势检验无统计学意义。
在西方人群中，高摄入异黄酮或哺乳动物木脂素与乳腺癌风险无显著关联。
