对整个地球都受益的营养指南：健康环境都有益

　　You know those nutrition guidelines the government issues every few years? It turns out that following them isn’t just good for your health. It’s good for the planet, too.

　　你知道政府每隔几年发布的营养指南吗?事实证明，听他们的，不仅对你的健康有好处，对整个地球也是好事。

　　“What we found is that impacts vary across nations, but in the high-impact nations, in general, you can see that, if you follow a nationally recommended diet, despite the fact that these diets don’t mention explicitly—or most of them don’t explicitly mention—environmental impacts, that you are going to have lower environmental impacts due to that. So that’s sort of fairly clear across all the high-income nations.”

　　“我们发现，这份营养指南在不同的国家产生的影响不同，但是在高影响力的国家，一般来说，如果遵循国家推荐的饮食指南，尽管事实上这些饮食没有明确提及——或者他们中的大部分都没有明确提及——环境影响——因为你的践行而对环境造成的更低的影响。这在所有高收入国家都是非常清楚的。“

　　Paul Behrens, an environmental scientist at Leiden University in the Netherlands. The food we eat takes a big toll on the environment. A third of the ice-free land on Earth is used for agriculture, and according to some estimates, producing food accounts for roughly a fifth of all human-caused greenhouse gas emissions. Fertilizer runoff also leads to other problems, like the algae blooms in Lake Eerie and the Dead Zone in the Gulf of Mexico.

　　Paul Behrens是荷兰莱顿大学环境科学家。我们吃的食物对环境造成很大的影响。地球上三分之一的无冰地带被用于农业耕种。根据统计估算，生产食物占所有人为温室气体排放量的大约五分之一。肥料径流也会导致其他问题，如墨西哥湾的怪异湖泊和死亡地带的藻类繁殖等问题。

　　However, following dietary guidelines would reduce those impacts, especially in wealthy countries like the US. “Most of the reductions come from meat and dairy,” which have an outsized impact on land use and pollution, and are a major source of greenhouse gases. (That’s partly due to cow farts. Seriously.) Heeding recommendations would also mean eating fewer calories, since many people here eat more than they need.

　　然而，遵循饮食指南会减少这些影响，特别是在像美国这样的发达国家。“大部分减排来自肉类和奶制品”，这对土地使用和污染有非常大的影响，因为这些是温室气体的主要来源。 (这部分是由于牛屁排放造成的，真的)。听取建议也意味着摄入更少的卡路里，因为这里的许多人吃超量了。

　　Overall, in high-income countries, Behren’s team estimates that following the rules could result in as much as a 17 percent reduction in land use, a 21 percent reduction in nutrient pollution, and a 25 percent drop in agricultural greenhouse gas emissions. Cutting down on how much food we waste—which is roughly a third in the U.S.—could help even more. The results are in the Proceedings of the National Academy of Sciences. [Paul Behrens et al., Evaluating the environmental impacts of dietary recommendations]

　　总体而言，在发达国家，Behren研究小组估计，按照这些规定，土地使用量可能减少17%，营养物质污染减少21%，农业温室气体排放量减少25%。减少食物浪费可以帮助——美国三分之一——甚至更多的人们。该研究结果发表在“美国科学院学报”上。 [Paul Behrens等，评估饮食建议的环境影响]

　　Of course, people are notoriously bad at following diets. But: “These nationally recommended guidelines do actually have a knock-on effect to other areas of policy making. So if I’m developing a new healthy-eating-for-schools program then that’s going to be based off a lot of detail that I get from the nationally recommended guidelines. So while it might not necessarily be the case that people follow directly…they actually are quite influential on the preparation of other advice.”

　　当然，人们在遵守饮食方面做得很不到位。 但是：“这些国家推荐的指导方针实际上对其他决策领域也有着连锁反应。因此，如果我正在制定一个新的健康饮食学校计划，那么这将以我从国家推荐的指导方针中得到的许多细节为参考依据。所以，虽然不一定是人们直接根据营养指南来做，但是他们在准备其他建议方面实际上是非常有影响力的。"

　　Seems that a smaller environmental footprint and a healthier lifestyle could go hand in hand.

　　这样说来，更少的环境足迹和更健康的生活方式可以携手共进。