Lampe Johanna W, Huang Ying, Neuhouser Marian L, Tinker Lesley F, Song Xiaoling, Schoeller Dale A, Kim Soyoung, Raftery Daniel, Di Chongzhi, Zheng Cheng, Schwarz Yvonne, Van Horn Linda, Thomson Cynthia A, Mossavar-Rahmani Yasmin, Beresford Shirley Aa, Prentice Ross L
Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA;
School of Public Health and.
Am J Clin Nutr. 2017 Feb;105(2):466-475. doi: 10.3945/ajcn.116.144840. Epub 2016 Dec 28.
Controlled human feeding studies are necessary for robust nutritional biomarker development and validation. Previous feeding studies have typically evaluated single nutrients and tested relatively few diets.
The objectives were 1) to simultaneously associate dietary intake with a range of potential nutritional biomarkers in postmenopausal women by using a controlled feeding study whereby each participant was provided a diet similar to her usual diet and 2) to evaluate serum concentrations of select nutrients as potential biomarkers with the use of established urinary recovery biomarkers of energy and protein as benchmarks for evaluation.
Postmenopausal women from the Women's Health Initiative (n = 153) were provided with a 2-wk controlled diet in which each individual's menu approximated her habitual food intake as estimated from her 4-d food record and adjusted for estimated energy requirements. Serum biomarkers, including carotenoids, tocopherols, folate, vitamin B-12, and phospholipid fatty acids, were collected at the beginning and end of the feeding period. Doubly labeled water and urinary nitrogen biomarkers were used to derive estimates of energy and protein consumption, respectively.
Linear regression of (ln-transformed) consumed nutrients on (ln-transformed) potential biomarkers and participant characteristics led to the following regression (R) values for serum concentration biomarkers: folate, 0.49; vitamin B-12, 0.51; α-carotene, 0.53; β-carotene, 0.39; lutein + zeaxanthin, 0.46; lycopene, 0.32; and α-tocopherol, 0.47. R values for percentage of energy from polyunsaturated fatty acids and urinary recovery biomarkers of energy and protein intakes were 0.27, 0.53, and 0.43, respectively. Phospholipid saturated fatty acids and monounsaturated fatty acids and serum γ-tocopherol were weakly associated with intake (R < 0.25).
Serum concentration biomarkers of several vitamins and carotenoids performed similarly to established energy and protein urinary recovery biomarkers in representing nutrient intake variation in a feeding study, and thus are likely suitable for application in this population of postmenopausal women. Further work is needed to identify objective measures of categories of fatty acid intake. This trial was registered at clinicaltrials.gov as NCT00000611.
对于可靠的营养生物标志物的开发和验证而言，人体对照喂养研究是必要的。以往的喂养研究通常评估单一营养素，且测试的饮食种类相对较少。
目标如下：1）通过一项对照喂养研究，使绝经后女性的饮食摄入量与一系列潜在的营养生物标志物建立关联，在该研究中，为每位参与者提供与其日常饮食相似的饮食；2）以既定的能量和蛋白质尿回收率生物标志物作为评估基准，评估选定营养素的血清浓度作为潜在生物标志物。
从女性健康倡议组织中招募了153名绝经后女性，为她们提供为期2周的对照饮食，其中每个人的菜单接近根据其4天食物记录估算的习惯性食物摄入量，并根据估算的能量需求进行调整。在喂养期开始和结束时收集血清生物标志物，包括类胡萝卜素、生育酚、叶酸、维生素B-12和磷脂脂肪酸。分别使用双标水和尿氮生物标志物来估算能量和蛋白质消耗。
（经自然对数转换的）摄入营养素与（经自然对数转换的）潜在生物标志物及参与者特征之间的线性回归得出了血清浓度生物标志物的以下回归（R）值：叶酸为0.49；维生素B-12为0.51；α-胡萝卜素为0.53；β-胡萝卜素为0.39；叶黄素+玉米黄质为0.46；番茄红素为0.32；α-生育酚为0.47。来自多不饱和脂肪酸的能量百分比以及能量和蛋白质摄入量的尿回收率生物标志物的R值分别为0.27、0.53和0.43。磷脂饱和脂肪酸和单不饱和脂肪酸以及血清γ-生育酚与摄入量的关联较弱（R<0.25）。
在一项喂养研究中，几种维生素和类胡萝卜素的血清浓度生物标志物在反映营养素摄入变化方面的表现与既定的能量和蛋白质尿回收率生物标志物相似，因此可能适用于该绝经后女性群体。需要进一步开展工作以确定脂肪酸摄入量类别的客观测量方法。该试验已在clinicaltrials.gov上注册，注册号为NCT00000611。
