Lewis S J, Heaton K W, Oakey R E, McGarrigle H H
University Department of Medicine, Bristol Royal Infirmary, UK.
Br J Cancer. 1997;76(3):395-400. doi: 10.1038/bjc.1997.397.
Increased fibre intake has been shown to reduce serum oestrogen concentrations. We hypothesized that fibre exerts this effect by decreasing the time available for reabsorption of oestrogens in the colon. We tested this in volunteers by measuring changes in serum oestrogen levels in response to manipulation of intestinal transit times with senna and loperamide, then comparing the results with changes caused by wheat bran. Forty healthy premenopausal volunteers were placed at random into one of three groups. The first group took senna for two menstrual cycles then, after a washout period, took wheat bran, again for two menstrual cycles. The second group did the reverse. The third group took loperamide for two menstrual cycles. At the beginning and end of each intervention a 4-day dietary record was kept and whole-gut transit time was measured; stools were taken for measurement of pH and beta-glucuronidase activity and blood for measurement of oestrone and oestradiol and their non-protein-bound fractions and of oestrone sulphate. Senna and loperamide caused the intended alterations in intestinal transit, whereas on wheat bran supplements there was a trend towards faster transit. Serum oestrone sulphate fell with wheat bran (mean intake 19.8 g day(-1)) and with senna; total- and non-protein-bound oestrone fell with senna. No significant changes in serum oestrogens were seen with loperamide. No significant changes were seen in faecal beta-glucuronidase activity. Stool pH changed only with senna, in which case it fell. In conclusion, speeding up intestinal transit can lower serum oestrogen concentrations.
已有研究表明，增加膳食纤维摄入量可降低血清雌激素浓度。我们推测，膳食纤维是通过减少雌激素在结肠的重吸收时间来发挥这一作用的。我们通过测量志愿者在服用番泻叶和洛哌丁胺以控制肠道转运时间后血清雌激素水平的变化来验证这一推测，然后将结果与麦麸引起的变化进行比较。40名健康的绝经前志愿者被随机分为三组。第一组服用番泻叶两个月经周期，然后在洗脱期后服用麦麸，同样为两个月经周期。第二组则相反。第三组服用洛哌丁胺两个月经周期。在每次干预开始和结束时，记录4天的饮食情况并测量全肠道转运时间；采集粪便测量pH值和β-葡萄糖醛酸酶活性，采集血液测量雌酮、雌二醇及其非蛋白结合部分以及硫酸雌酮。番泻叶和洛哌丁胺引起了肠道转运的预期改变，而服用麦麸补充剂时有转运加快的趋势。服用麦麸（平均摄入量19.8克/天）和番泻叶后血清硫酸雌酮下降；服用番泻叶后总雌酮和非蛋白结合雌酮下降。服用洛哌丁胺后血清雌激素未见显著变化。粪便β-葡萄糖醛酸酶活性未见显著变化。仅服用番泻叶时粪便pH值发生变化，此时pH值下降。总之，加快肠道转运可降低血清雌激素浓度。
