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The global food system, from fertilizer manufacture to food storage and packaging, is responsible for up to a staggering one-third of all human-caused GHG emissions. Although there is a need to make food systems more efficient and sustainable, this in itself is not adequate to bring GHG emissions down to acceptable levels; changes also need to be made to our diets.

但是需要哪些更改？美国国家公共卫生与环境研究所（RIVM）的Elisabeth Temme及其同事通过查看荷兰的食品消费，在荷兰的食物消费中，在荷兰的食物消费中，水果和蔬菜的摄入量很低，饱和脂肪酸的摄入量很低钠很高。

消费数据是从荷兰的最新食品消费调查中获得的，荷兰国家食品消费调查（DNFCS）2007- 2010年。所有消费量都被标记为七个食品消费场合之一，区分三餐（早餐，午餐，晚餐）和两餐之间的所有时刻（早餐前，早餐和午餐之间，午餐和晚餐之间，晚餐后，晚餐后）。还获得了社会人口统计学和生活方式数据，例如体育活动和教育水平。

In order to estimate GHG emissions associated with different foods, life cycle assessments were performed; these look at the entire life cycle of a product from primary production, processing, use of packaging and transport to storage as well as the preparation of the food. The GHG emissions associated with the preparation of foods in the consumer phase was based on the average cooking time for each product . Food waste was also included by using food group specific percentages for avoidable and unavoidable food losses throughout the food chain, including the consumer phase.

The researchers found that, in the Dutch diet, the GHG emission varies per consumption occasion. In the highest tertile of dietary GHG emission, dinner was associated with the highest GHG emissions, and consumptions in between meals were associated with the second-to-highest emissions. Meat consumption contributed most to the GHG emission of dinner, while beverages contributed most to the GHG emission of consumptions in between meals. Dairy (including cheese) was an important contributor to total daily dietary GHG emission throughout the day.

The authors also developed various scenarios to lower GHG emissions of people in the highest tertile of dietary GHG emission: 1) reduce red and processed meat consumed during dinner by 50% and 75%, 2) replace 50% and 100% of alcoholic and soft drinks (including fruit and vegetable juice and mineral water) by tap water, 3) replace cheese consumed in between meals by plant-based alternatives and 4) two combinations of these scenarios. Effects on GHG emission as well as nutrient content of the diet were assessed.

The most effective single dietary change was to reduce the consumption of meat, with a 75% reduction in red and/or processed meat during dinner resulting in a 24% reduction in GHG emissions for men and a 22% reduction for women. Furthermore, replacing the consumption of all alcoholic drinks and soft drinks (including mineral water and fruit and vegetable juices) with tap water was also successful in reducing dietary GHG emissions.

The dietary changes are also beneficial for health as they are more in line with dietary guidelines and reduce saturated fatty acids and sugar intake. For those who may not meet energy or iron requirements with these changes in diet, low GHG emission and nutritious replacement foods might be needed.

尽管这项研究的情况集中在温室气体排放最高的人中，但预计此处提出的饮食变化也将导致减少最低或中间三物的人的温室气体排放。但是，需要进一步的研究来确定是否确实如此。