Genes & Nutrition
国际前沿|海外食品华人协会 学术速递 专栏 点击了解
编译：海外食品人 | 周小敏
你记得昨天晚餐吃了什么吗？
你记得这顿晚餐你吃了多少吗？
在不同季节，你会有不同的饮食习惯吗？
其实，我们很难完整地回忆和记录这些跟饮食相关的具体信息，而这样的问题是营养学研究中常用的数据收集手段。显而易见，这样方法是非常依赖于个人记忆、经验和知识，是比较主观的、易产生误差的饮食记录方法。因此，如何客观准确记录志愿者的饮食结构和饮食量，进而客观地阐述饮食和健康、疾病的关系，是营养学研究领域所面临的挑战之一。
小编在此翻译和分享其博士导师LaLars Ove Dragsted发表的关于如何验证BFIs综述文章一篇。虽然这不是最新的文章，但反映的是非常新的、有创意的且存在巨大挑战的研究方向。小编的博士课题方向为营养代谢组学，与大部分团队成员致力于发现和鉴定biomarkers of food intake （BFIs）这一由欧盟赞助的项目。Candidate BFIs发现后，需要进行相关验证和论证，与传统的饮食记录方法结合，运用于实际的临床试验中来评估饮食和健康的关系。
分享文献：Validation ofbiomarkers of food intake—critical assessment of candidate biomarkers
注：小编的另一篇博士论文【学术速递】尿液代谢组学分析揭示了不同热加工土豆膳食干预后的生物印记 也是该领域的研究，有兴趣的可以查看。
● 成果介绍
摘要：
在营养学研究中，相较于主观饮食记录方法，Biomarkers of food intake (BFIs)是寄予了能够减弱饮食评估误差的厚望。在饮食干预过程中，BFIs也可用于监测志愿者的饮食服从性。因此，BFIs具备直接和客观检测食物摄入的特性。
然而，经综合全面验证的BFIs较少。一些新的candidateBFIs主要来源于代谢物图谱的分析和食品化学的研究，和从系统的文献检索过程中提取而来。为了系统地、批判性地评估BFIs的有效性，精简地罗列出具可重复性并可调整的BFIs验证准则就显得非常有必要。
我们提供了一套系统的验证BFIs的方法，包括了很重要的验证准则。验证方法包含了8项准则，主要是合理性（更确切地是说特异性）、剂量效应、时间效应、稳健性、可靠性、稳定性、分析性能和不同实验室间的可重复性。
这个验证系统目的有二：（1）评估目前的candidateBFIs达到的验证水平；（2）阐述candidate BFIs未来还需要做哪些研究来达到充分验证的目的。
BFIs验证的八个准则
验证准则
验证问题，回答‘是’的准则说明
1. 合理性
问题：这个candidate BFIs是特异于某一食物或食物组吗？
((The BFI is likely to be a metabolite or process-related derivative of a compound known to occur in the food or food group) OR (the BFI has been identified as a putative biomarker for the food/food group) OR (the compound was identified as a putative biomarker in a metabolomics investigation))
AND (variability of (parent) compound within food or food group (if known) is limited)
AND ((the level of the (parent) compound in other foods is comparatively low) OR (presence only in other foods not commonly consumed))
2. 剂量效应
问题：存在剂量效应吗？（定量角度，摄入特定食物是否发生相应代谢物含量变化）
(The dose-response relationship of the BFI has been established using several intake levels (in a meal study) OR (in different meal studies where the results were comparable) OR (in cross-sectional study or longitudinal observational studies))
AND (the background level of the BFI is 0 or low)
Information about the limits for common background levels and saturation kinetics of the BFI should be provided as a comment
3. 时间效应
问题：BFIs的动力学是否充分描述？这样帮助我们更明智地选择样品类型和采样时间。
a. (The single-meal time-response relationship of the BFI has been described for a defined sample type and time window in a meal study) OR
b. (The kinetics of the BFI after repeated intakes has been described for a defined sample type in a meal study) OR (accumulation of the BFI in certain sample types has been observed)
Information about ADME and enzyme induction, inhibition, or altered excretion in the metabolism of the BFI or its precursor could be provided as a comment.
4. 稳健性
问题：在特定人群中，志愿者摄入混合食物反映自身饮食习惯，该BFI是否还能表现出稳健性？
((The BFI has been measured and shown to be robust after intake of complex meals (in intervention studies) OR (in observational studies))
AND ((There is no confounding food observed) OR (The level of the BFI from the confounding food is low) OR (The confounding foods are not commonly consumed))
5. 可靠性
问题：该BFI如果与其他BFIs或问卷调查数据相比，是否能有好的比较性？
(The BFI has been compared well (with other biomarkers for the same food or food group) OR (with dietary assessment instruments) OR (with data in studies with highly controlled setting and supervised intake)
6. 稳定性
问题：在生物样品收集、储存、检测过程稳定性和可行性方面，该BFI是否具备生物和化学稳定性？
(The BFI is chemically and biologically stable during biospecimen collection, processing and storage) OR (The BFI is not stable but suitable protocol has been established to achieve the stabilisation of the BFI)
7. 分析性能
问题：分析变异性、精确性、灵敏性和特性性如何（分析性能）？
(The protocol of the method has been well described and could be repeated)
AND (The method has been compared with validated method or references)
AND (The analytical variability (CV%), accuracy, sensitivity and specificity have been described)
8. 可重复性
问题：分析是否可以在另一个实验室进行重复？
(The analysis with the same method has been performed in at least 2 different laboratories)
AND (The measurements of the BFI obtained from different laboratories are comparable)
Comments