University of Massachusetts Amherst, Amherst, Massachusetts 01003-9304, USA.
Nutr Cancer. 2010;62(2):175-80. doi: 10.1080/01635580903305342.
Flaxseed is a rich source of dietary lignans. It has been hypothesized that lignans may decrease breast cancer risk through modulation of endogenous hormone levels. The aim of this study was to determine the effect of flaxseed supplementation on urinary levels of estrogen metabolites that may be involved in the development of breast cancer. Forty-three postmenopausal women participated in this 12-wk preintervention-postintervention study. Participants consumed 7.5 g/day of ground flaxseed for 6 wk, followed by 15 g/day for an additional 6 wk. The mean urinary level of 16alpha -hydroxyestrone (16alpha -OHE1) was higher at the end of 12 wk compared to baseline (change of 1.32 ug/day, P = 0.02). There was no significant change in 2-OHE1 excretion. The mean urinary level of the 2-OHE1/16alpha -OHE1 ratio was lower at the end of 12 wk compared to baseline (change of -1.1, P = 0.02). Mean urinary excretion of 2-methoxyestradiol was also lower at 12 wk than at baseline (P = 0.03). Based on the current paradigm of the effects of estrogen metabolism on breast cancer risk, the regimen of dietary flaxseed intake used in this study did not appear to favorably alter breast cancer risk through shifts in estrogen metabolism pathways in postmenopausal women.
亚麻籽是膳食纤维木脂素的丰富来源。有人假设木脂素可能通过调节内源性激素水平来降低乳腺癌的风险。本研究的目的是确定亚麻籽补充剂对可能参与乳腺癌发展的尿雌激素代谢物水平的影响。43 名绝经后妇女参加了这项为期 12 周的干预前-干预后研究。参与者每天食用 7.5 克磨碎的亚麻籽 6 周，然后再食用 15 克亚麻籽 6 周。与基线相比，12 周末 16α-羟雌酮（16α-OHE1）的平均尿水平更高（变化 1.32ug/天，P=0.02）。2-OHE1 排泄没有明显变化。与基线相比，12 周末 2-OHE1/16α-OHE1 比值的平均尿水平更低（变化-1.1，P=0.02）。12 周时 2-甲氧基雌二醇的平均尿排泄也低于基线（P=0.03）。根据目前关于雌激素代谢对乳腺癌风险影响的范式，本研究中使用的饮食亚麻籽摄入方案似乎并没有通过改变绝经后妇女的雌激素代谢途径来有利地改变乳腺癌风险。
