Division of Adolescent and Transition Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio.
Schubert Research Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
J Adolesc Health. 2022 Mar;70(3):483-487. doi: 10.1016/j.jadohealth.2021.10.011. Epub 2021 Nov 24.
Increased fiber intake has been associated with decreased breast cancer risk, while increased animal protein intake with increased risk. The objective of this study is to examine the relationship of dietary fiber and protein intake to estrogen and sex hormone-binding globulin (SHBG) concentrations at puberty onset.
These analyses were conducted using the Cincinnati puberty cohort of the Breast Cancer and the Environment Research Program, with girls followed every 6 months from ages 6 and 7. The analyses included serum measurements at 6-month intervals for estrogen and SHBG concentrations, from 18 months prior to breast stage 2 (onset of puberty). Dietary intake was documented via 24-hour dietary recalls every 3 months. Dietary factors of interest included total energy intake; total and animal protein; total, soluble, and insoluble fiber; and lignan and flavanol intake.
This study included 260 participants who generated 871 serum specimens and 3,000 days of diet intake. In longitudinal models, estradiol was associated inversely with insoluble fiber intake; estrone positively with animal protein intake; SHBG with greater insoluble fiber and lower total protein intake; and ratio of estrone to SHBG, a measure of bioavailable estrogen, positively with animal protein.
Greater protein intake, especially animal protein, led to greater estrogen concentrations and lower SHBG; greater animal protein and greater caloric intake led to increased bioavailable estrogen. This relationship may have served an evolutionary advantage in the past for greater fertility with adequate high-quality protein; in contemporary women, a modest decrease in animal protein may be beneficial in reducing breast cancer risk.
增加膳食纤维的摄入量与降低乳腺癌风险有关，而增加动物蛋白的摄入量则与增加风险有关。本研究的目的是研究膳食纤维和蛋白质的摄入量与青春期开始时的雌激素和性激素结合球蛋白（SHBG）浓度的关系。
这些分析是使用 Breast Cancer and the Environment Research Program 的辛辛那提青春期队列进行的，从 6 岁和 7 岁开始，每 6 个月对女孩进行一次随访。分析包括在乳房 2 期（青春期开始）前 18 个月开始，每隔 6 个月进行一次雌激素和 SHBG 浓度的血清测量。通过每 3 个月进行一次 24 小时膳食回忆来记录膳食摄入情况。感兴趣的饮食因素包括总能量摄入；总蛋白和动物蛋白；总纤维、可溶性纤维和不溶性纤维；以及木脂素和黄烷醇的摄入量。
本研究包括 260 名参与者，他们共生成了 871 份血清样本和 3000 天的饮食摄入数据。在纵向模型中，雌二醇与不溶性纤维摄入呈负相关；雌酮与动物蛋白摄入呈正相关；SHBG 与更多的不溶性纤维和更低的总蛋白摄入呈负相关；而雌酮与 SHBG 的比值，即生物可利用雌激素的衡量指标，与动物蛋白呈正相关。
更多的蛋白质摄入，尤其是动物蛋白，导致更高的雌激素浓度和更低的 SHBG；更多的动物蛋白和更高的热量摄入导致更多的生物可利用雌激素。这种关系在过去可能为生育能力提供了足够的优质蛋白质的优势；在当代女性中，适度减少动物蛋白可能有助于降低乳腺癌风险。
