其他工业国家的情况也是一样，随之而来的不仅是肥胖率的增高，癌症和心脏病的发病率也在不断攀升。通常来说，每人每天食用红肉或加工肉制品的总量应不超过70克，相当于一小份汉堡的量。

不同于西方国家，中国的肉类消费水平相对较低。中国人平均每天的肉类消费仅比健康标准高1.5倍。但考虑到文化、经济和地域等因素的差异，仅用这一数值来衡量整个国家的水平还是过于简单化。

肉类及加工肉制品消费增加的同时，运动量却在减少，使得现今中国的超重人口比营养不良人口多了一倍。中国国内消费和出口的肉制品产量也在不断攀升，从1978年的850万吨增长至2011年的7950万吨，年均增长率达6.93%。到目前为止，促进肉类消费仍是政府的一项国策。

畜牧养殖业的二氧化碳排放占全球二氧化碳排放总量的15%，同运输业尾气排放量相当。然而，却很少有人了解饮食与气候变化之间的联系。政府担心干预人们的饮食会引起公众的强烈反对，因而在探讨气候变化的解决方案时，政府从不会将重点放在减少肉类消费上。今日新发布的一份报告指出，必须纠正这一做法。但这并不是要求人们以后都只吃素食，而是让人们向健康的饮食习惯靠拢，向肉类健康消费标准看齐。

查塔姆研究所在研究过程中，曾在12个国家进行了网上调查，还分别在中国、巴西、英国和美国这四个国家成立了四个深入调查小组，探究政府为扭转公众行为所采取的措施。同时，他们的调查还发现，虽然所有接受调查的人都认为改变人们的饮食习惯存在着很大的难度，但不同国家的人对肉类食品的态度不同。

鉴于中国肉类消费水平较低，经济起步较晚这一状况，接受调查的中国人都认为要求他们减少肉食摄入是“不公平的”，其中一人甚至说到，“政府不会那么糊涂（到让人们改变饮食习惯）。”这些事实反应出，肉类消费在中国和巴西其实是代表了社会和经济的进步，越富有的人对肉类食品的需求就越大。

肉类对气候变化的影响并未受到中国政府的重视。人们对此也知之甚微，很少会将二者联系在一起。虽然参与调查的中国人对此的了解少于其他国家，但当相关数据摆在他们面前时，中国人对改变饮食结构的接受度却更高。究其原因，一部分可能与城市居民的“生活体验”相关，人们将严重的大气污染同气候变化联系在一起，因此愿意从个人做起减少污染。同时，这也反应出了中国人对于权威和科学的十足信任。

重要的是，在上述这四个国家中，接受调查的人都说，如果政府出台新政，鼓励人们改变饮食习惯，最初反对之声会慢慢减弱，越来越多的人将愿意去适应变化。人们对禁烟令等公共健康干预政策的态度都经过了相似的变化过程。因此，若政府认为改变公众饮食习惯太过困难，那就大错特错了。

中国还具备一个十分有力的条件，那就是传统的饮食习惯本身就以蔬菜和谷物为主，倡导减少肉类食用，因而实现肉食与蔬菜的均衡摄入并非难事。在中国，有不少食品可以替代肉类和奶制品。为了治疗贫血，中国还曾向食品中添加过铁元素。这就意味着中国肉类消费的峰值（同日本一样）有可能会低于西方国家，并成为全世界做出表率。如果每个人的饮食习惯都更加“中式化”，那么世界都有可能变得更加可持续。

翻译：吕嘉

安东尼·弗罗加，英国皇家国际事务研究所（查塔姆研究所）的能源、环境与发展项目高级研究员

The days of the 'Big Mac' may be numbered. Global per capita meat consumption is already higher than healthy levels, and is set to rise by 76% by 2050. This is unsustainable and poses significant threats to global health and the planet. In the US, the average person consumes three times more meat than health experts recommend.

Per capita consumption is significantly above recommended levels in other industrialised countries too, where it is associated with rising levels of obesity, cancer and heart disease. A rough rule of thumb is that people should aim to eat no more than 70g of red or processed meat a day - about the same as a small hamburger.

The picture is a bit different in China, where meat consumption is lower than in the West. On average, Chinese people eat about one and a half times as much meat every day as recommended, although aggregate levels are an overly simplistic measure given the country’s cultural, economic and geographical diversity.

The impact of rising consumption of meat (and processed foods) coupled with a lack of exercise is being felt: there are now approximately twice as many overweight as malnourished people in China. Levels of Chinese meat production – for domestic consumption and export – are also rising. In 1978, China's meat production was 8.5 million tonnes. By 2011, it had reached 79.5 million, an average annual increase of almost 7%. And until recently, increasing meat consumption was an explicit government strategy.

Globally, the livestock sector accounts for 15% of carbon dioxide emissions – as much the exhaust fumes from all forms of transport. And yet public awareness of the link between diet and climate is very low. Governments are afraid of the backlash if they tell people what to eat and as a result  place very little emphasis on reducing meat consumption when talking about the solutions to climate change. A new report out today argues that this must change. This does not mean everyone should become vegetarian. Rather, they should shift to healthy diets, and reduce the amount of meat that is consumed, to bring it in line with recommended levels.

In researching the report, Chatham House carried out an online survey in 12 countries, and in-depth focus groups in China, Brazil, the UK and US. The focus groups threw light on what governments will need to do to shift public behaviour. They also revealed interesting differences between people’s attitudes to meat in different countries - though all respondents identified strong social barriers to changing diets.

Changing behaviour

In light of their lower aggregate consumption levels and China’s later economic development, Chinese participants tended to think that asking people to reduce their meat eating would be ‘unfair’. One respondent said that ‘governments wouldn’t be that stupid’. This reflects the fact that in China – and Brazil – meat consumption is seen as a sign of social and economic progress, with wealthier respondents expressing a desire to eat more meat.

The impact of meat on climate change is not on the public agenda in China. There is a low level of public knowledge about this issue and a high degree of confusion. However, while Chinese participants tended to know less than people in other countries about the link between diet and climate change, they were more likely to be prepared to change their diets on being presented with the facts. This may in part be to do with the ‘lived experience' of Chinese people in urban areas, who associate high levels of atmospheric pollution with climate change, and are ready to take individual action to reduce this. It also reflects higher levels of trust in the authorities, and lower scepticism about science.

Intervention

Importantly, respondents in all focus group countries said that if governments did introduce new policies to encourage a change in diet, the initial resistance would subside and people would go along with the changes, as they have with other public health interventions, such as restrictions on smoking. This suggests that governments’ assumption that effecting dietary change is too difficult is unjustified.

A particular cause for optimism in China is that the traditional diet lends itself to reduced meat content. It is heavy in vegetables and grains, and achieving a sustainable meat to plant ratio is not difficult. There are also many alternatives to meat and dairy and a history of fortification of food products with iron to address anaemia. This means that China’s meat consumption (like Japan’s) is likely to peak at lower levels than in the West. It also suggests that China could set an example to the rest of the world. If everyone ate a more ‘Chinese’ diet we might be able to feed the world sustainably.

The full report: Changing Climate, Changing Diets: Pathways to Lower Meat Consumption