Interfaculty Initiative in Information Studies, University of Tokyo, Tokyo, 113 0033, Japan.
Northern Ireland Centre for Food and Health, Ulster University, Coleraine, BT52 1SA, UK.
Nutr J. 2018 Feb 21;17(1):27. doi: 10.1186/s12937-018-0338-x.
While the admittedly limited number of epidemiological findings on the association between diet-related greenhouse gas emissions (GHGE) and diet quality are not always consistent, potential influence of bias in the estimation of diet-related GHGE caused by misreporting of energy intake (EI) has not been investigated. This cross-sectional study evaluated diet-related GHGE in the UK and their association with diet quality, taking account of EI under-reporting.
Dietary data used were from the National Diet and Nutrition Survey rolling programme 2008/2009-2013/2014, in which 4-day food diaries were collected from 3502 adults aged ≥19 years. Diet-related GHGE were estimated based on 133 food groups, using GHGE values from various secondary sources. Diet quality was assessed by the healthy diet indicator (HDI), Mediterranean diet score (MDS) and Dietary Approaches to Stop Hypertension (DASH) score. EI misreporting was assessed as reported EI divided by estimated energy requirement (EI:EER).
Mean value of daily GHGE was 5.7 kg carbon dioxide equivalents (COeq), which is consistent with those reported from a number of national representative samples in other European countries. Mean EI:EER was 0.74. Assuming that all the dietary variables were misreported in proportion to the misreporting of EI, the mean value of the misreporting-adjusted diet-related GHGE was 8.2 kg COeq/d. In the entire population, after adjustment for potential confounders (i.e., age, sex, ethnicity, socioeconomic classification, smoking status and physical activity), diet-related GHGE were inversely associated with HDI and DASH score but not with MDS. However, with further adjustment for EI:EER, diet-related GHGE showed inverse associations with all three measures of diet quality. Similar associations were observed when only under-reporters (EI:EER < 0.70; n = 1578) were analysed. Conversely, in the analysis including only plausible reporters (EI:EER 0.70-1.43; n = 1895), diet-related GHGE showed inverse associations with all diet quality measures irrespective of adjustment.
With taking account of EI under-reporting, this study showed inverse associations between diet-related GHGE and diet quality not only in the entire sample but also in the separate analyses of plausible reporters and under-reporters, as well as potential underreporting of diet-related GHGE.
虽然与饮食相关的温室气体排放（GHGE）与饮食质量之间关联的流行病学研究结果数量有限，而且并不总是一致，但由于能量摄入（EI）报告不准确而导致饮食相关 GHGE 估计中存在的偏倚的潜在影响尚未得到调查。本横断面研究考虑了 EI 低报的情况，评估了英国与饮食相关的 GHGE 及其与饮食质量的关联。
本研究使用的饮食数据来自于 2008/2009 年至 2013/2014 年期间的国家饮食与营养调查滚动项目，其中从 3502 名年龄≥19 岁的成年人中收集了 4 天的饮食日记。基于各种次要来源的 GHGE 值，使用 133 种食物组来估算与饮食相关的 GHGE。通过健康饮食指标（HDI）、地中海饮食评分（MDS）和停止高血压的饮食方法（DASH）评分来评估饮食质量。EI 低报的情况通过报告的 EI 除以估计的能量需求（EI：EER）来评估。
每日 GHGE 的平均值为 5.7 千克二氧化碳当量（COeq），与其他欧洲国家的一些全国代表性样本报告的值一致。EI：EER 的平均值为 0.74。假设所有饮食变量都按照 EI 低报的比例进行错误报告，则错误报告调整后的与饮食相关的 GHGE 的平均值为 8.2 千克 COeq/d。在整个人群中，在调整了潜在混杂因素（即年龄、性别、种族、社会经济分类、吸烟状况和身体活动）后，与饮食相关的 GHGE 与 HDI 和 DASH 评分呈负相关，但与 MDS 无关。然而，进一步调整 EI：EER 后，与饮食相关的 GHGE 与所有三种饮食质量测量指标均呈负相关。仅在低报者（EI：EER<0.70；n=1578）中进行分析时观察到类似的关联。相反，在包括仅合理报告者（EI：EER 0.70-1.43；n=1895）的分析中，无论是否进行调整，与饮食相关的 GHGE 与所有饮食质量指标均呈负相关。
本研究考虑了 EI 低报的情况，结果表明，与饮食相关的 GHGE 与饮食质量之间不仅在整个样本中存在负相关，而且在合理报告者和低报者的单独分析中，以及与饮食相关的 GHGE 的潜在低报中也存在负相关。
