Sjörs Camilla, Raposo Sara E, Sjölander Arvid, Bälter Olle, Hedenus Fredrik, Bälter Katarina
Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, SE-171 77, Stockholm, Sweden.
Current address: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, 02115, USA.
Environ Health. 2016 Feb 9;15:15. doi: 10.1186/s12940-016-0110-7.
The current food system generates about 25 % of total greenhouse gas emissions (GHGE), including deforestation, and thereby substantially contributes to the warming of the earth's surface. To understand the association between food and nutrient intake and GHGE, we therefore need valid methods to assess diet-related GHGE in observational studies.
Life cycle assessment (LCA) studies assess the environmental impact of different food items. We linked LCA data expressed as kg carbon dioxide equivalents (CO2e) per kg food product to data on food intake assessed by the food frequency questionnaire (FFQ) Meal-Q and validated it against a 7-day weighed food record (WFR). 166 male and female volunteers aged 20-63 years completed Meal-Q and the WFR, and their food intake was linked to LCA data.
The mean GHGE assessed with Meal-Q was 3.76 kg CO2e per day and person, whereas it was 5.04 kg CO2e using the WFR. The energy-adjusted and deattenuated Pearson and Spearman correlation coefficients were 0.68 and 0.70, respectively. Moreover, compared to the WFR, Meal-Q provided a good ranking ability, with 90 % of the participants classified into the same or adjacent quartile according to their daily average CO2e. The Bland-Altman plot showed an acceptable level of agreement between the two methods and the reproducibility of Meal-Q was high.
This is the first study validating the assessment of diet-related GHGE by a questionnaire. The results suggest that Meal-Q is a useful tool for studying the link between food habits and CO2e in future epidemiological studies.
当前的食物系统产生了约25%的温室气体排放总量（包括森林砍伐），从而极大地导致了地球表面变暖。因此，为了解食物和营养摄入与温室气体排放之间的关联，我们需要在观察性研究中采用有效的方法来评估与饮食相关的温室气体排放。
生命周期评估（LCA）研究评估不同食物的环境影响。我们将以每千克食品的二氧化碳当量（CO2e）表示的LCA数据与通过食物频率问卷（FFQ）Meal-Q评估的食物摄入量数据相联系，并根据7天称重食物记录（WFR）对其进行验证。166名年龄在20 - 63岁之间的男性和女性志愿者完成了Meal-Q和WFR，他们的食物摄入量与LCA数据相联系。
用Meal-Q评估的人均每日温室气体排放均值为3.76千克CO2e，而使用WFR时为5.04千克CO2e。能量调整和去衰减后的Pearson和Spearman相关系数分别为0.68和0.70。此外，与WFR相比，Meal-Q具有良好的排序能力，90%的参与者根据其每日平均CO2e被归类到相同或相邻的四分位数。Bland-Altman图显示两种方法之间的一致性水平可接受，且Meal-Q的可重复性较高。
这是第一项通过问卷验证与饮食相关的温室气体排放评估的研究。结果表明，在未来的流行病学研究中，Meal-Q是研究饮食习惯与CO2e之间联系的有用工具。
