文章来源：《经济学人》March 4th 2023 期 Leaders 栏目 Eat, inject, repeat

A new type of drug is generating excitement among the rich and the beautiful. Just a jab a week, and the weight falls off. Elon Musk swears by it; influencers sing its praises on TikTok; suddenly slimmer Hollywood starlets deny they have taken it. But the latest weight-loss drugs are no mere cosmetic enhancements. Their biggest beneficiaries will be not celebrities in Los Angeles or Miami but billions of ordinary people around the world whose weight has made them unhealthy.

一种新型药物在富人和美女中引起了轰动。每周注射一次，体重就会下降。埃隆·马斯克(Elon Musk)对它信誓旦旦;有影响力的人在TikTok上歌颂它；突然变得苗条的好莱坞小明星们都否认自己服用了这种药物。但是最新的减肥药不仅仅是美容。它们最大的受益者将不是洛杉矶或迈阿密的名人，而是全球数十亿因体重而不健康的普通人。

Treatments for weight loss have long ranged from the well-meaning and ineffective to the downright dodgy. The new class of drugs, called GLP-1 receptor agonists, seems actually to work. Semaglutide, developed by Novo Nordisk, a Danish pharmaceutical firm, has been shown in clinical trials to lead to weight loss of about 15%. It is already being sold under the brand name Wegovy in America, Denmark and Norway and will soon be available in other countries;  Ozempic, a lower-dose version, is a diabetes drug that is also being used “off label” for weight loss. A rival GLP-1 drug, made by Eli Lilly, an American firm, is due to come on sale later this year and is more effective still. Analysts think the market for GLP-1 drugs could reach $150bn by 2031, not far off the market for cancer drugs today. Some think they could become as common as beta blockers or statins.

长期以来，减肥的治疗方法从善意的、无效的到彻头彻尾的欺骗。这种被称为GLP-1受体激动剂的新型药物似乎确实有效。由丹麦诺和诺德制药公司开发的赛马鲁肽在临床试验中已显示可使体重减轻约15%。它已经以Wegovy的品牌在美国、丹麦和挪威销售，很快将在其他国家上市；Ozempic是一种低剂量的糖尿病药物，也被“非标签”用于减肥。美国Eli Lilly公司生产的GLP-1药物的竞争对手将于今年晚些时候上市，而且效果更好。分析师们认为，到2031年，GLP-1药物的市场规模可能达到1500亿美元，与目前抗癌药的市场规模相差不远。一些人认为它们可能会像受体阻滞剂或降低胆固醇药物一样普遍。

The drugs could not have arrived at a better time. In 2020 two-fifths of the world’s population were over weight or obese. By 2035, says the World Obesity Federation, an NGO, that figure could swell to more than half, with a staggering 4bn people overweight or obese. People everywhere are getting fatter. The populations putting on pounds the fastest are not in the rich West but in countries like Egypt, Mexico and Saudi Arabia.

药物来得正是时候。到2020年，全球五分之二的人口超重或肥胖。非政府组织世界肥胖联合会表示，到2035年，这一数字可能会膨胀到一半以上，超重或肥胖的人将达到惊人的40亿。世界各地的人都在变胖。体重增长最快的不是富裕的西方国家，而是埃及、墨西哥和沙特阿拉伯等国家。

These trends are alarming because obesity causes a host of health problems, including diabetes, heart disease and high blood pressure, as well as dozens of illnesses such as stroke, gout and various cancers. Carrying extra weight made people more likely to die of covid-19. And then there is the misery that comes from the stigma associated with being fat, which affects children in schools and playgrounds most cruelly of all.

这些趋势令人担忧，因为肥胖会导致一系列健康问题，包括糖尿病、心脏病和高血压，以及中风、痛风和各种癌症等数十种疾病。超重使人们更有可能死于covid-19。此外，肥胖还带来了耻辱，这种耻辱最残酷地影响着学校和操场上的孩子们。

The consequences of obesity for the public purse and the wider economy are large. According to modelling by academics the annual cost to the world economy of excess weight could reach $4trn by 2035 (2.9% of global GDP, up from 2.2% in 2019). That includes both spending on health care and working time lost to illness and premature deaths tied to obesity.

肥胖对公共财政和整体经济的影响是巨大的。根据学者们的建模，到2035年，超重对世界经济的年度成本可能达到4万亿美元(占全球GDP的2.9%，高于2019年的2.2%)。这既包括医疗保健支出，也包括因疾病和肥胖导致的过早死亡而损失的工作时间。

The world’s expanding waistlines are not a sign of the moral failure of the billions who are overweight, but the result of biology. The genes that were vital to helping humans survive winters and famine still help the body cling on to its weight today. The superabundance of hard-to-resist processed foods in recent decades has brought greater convenience and lower costs, but also triggered overeating just as lifestyles became more sedentary. Once the fat is on, the body fights any attempt to diet away more than a little of its total weight. Despite the $250bn that consumers around the world spent on dieting and weight loss last year, the battle to get slim was largely being lost.

世界上不断扩大的腰围并不是数十亿超重人群道德沦丧的标志，而是生物学的结果。那些帮助人类在冬天和饥荒中生存下来的重要基因，今天仍然帮助人体保持体重。近几十年来，令人难以抗拒的加工食品的过剩带来了更大的便利和更低的成本，但随着生活方式变得更久坐不动，也引发了暴饮暴食。一旦脂肪长出来，身体就会抵制任何减肥的企图。尽管去年全球消费者在节食和减肥上花费了2500亿美元，但减肥之战在很大程度上还是失败了。

The new obesity drugs arrived by serendipity, after treatments meant for diabetics were observed to cause weight loss. Semaglutide mimics the release of hormones that stimulate a feeling of fullness and reduce the appetite (see Briefing). They also switch off the powerful urge to eat that lurks inside the brain, waiting to ambush even the keenest dieter.

这种新型减肥药的出现纯属偶然，此前人们观察到针对糖尿病患者的治疗方法可以减轻体重。Semaglutide模拟激素的释放，刺激饱腹感并降低食欲(见简报)。它们还能切断潜藏在大脑中的强烈的吃东西的欲望，即使是最积极的节食者也会受到这种欲望的伏击。

With the jabs already in high demand, investors are nearly as giddy as newly slim users. The market capitalisation of Novo Nordisk, the firm at the front of the gold rush, has doubled in two years, to $326bn, making it the second-most-valuable listed drugmaker in the world (see Schumpeter). Analysts expect half of obese Americans who seek help to be on GLP-1 drugs by the turn of the decade. But, as with any new medicine that holds so much promise for so many, there are uncertainties. Two big ones will be safety and affordability.

由于注射疫苗的需求已经很高，投资者几乎和新减肥的用户一样兴奋。处于淘金热前沿的Novo Nordisk公司的市值在两年内翻了一番，达到3260亿美元，使其成为世界上市值第二高的上市制药商。分析人士预计，到2020年，半数寻求帮助的肥胖美国人将服用GLP-1药物。但是，就像任何对如此多的人有如此大希望的新药一样，也存在不确定性。两大问题是安全性和可承受性。

Consider safety first. The newness of these drugs means that their long-term consequences are not yet known. For the lower dose forms prescribed for diabetes, the side-effects, such as vomiting and diarrhoea, have been mild. But others could crop up as the drugs are used more widely and at higher doses. Animal studies have shown a higher incidence of thyroid cancer, and semaglutide is associated with a rare pancreatitis. Little is known about the effects of using them during or just before pregnancy. All this will require careful analysis through controlled longitudinal studies.

安全第一。这些药物的新特性意味着它们的长期后果尚不清楚。对于治疗糖尿病的低剂量药物，如呕吐和腹泻等副作用是轻微的。但随着药物的广泛使用和更高剂量的使用，其他药物可能会突然出现。动物研究表明甲状腺癌的发病率较高，而赛莫格拉肽与一种罕见的胰腺炎有关。很少有人知道在怀孕期间或怀孕前使用它们的效果。所有这些都需要通过受控纵向研究进行仔细分析。

Understanding these risks will be important, because many patients who take the drugs may need them for the rest of their lives. As with ditching a diet, stopping a high dose of semaglutide is associated with much of the lost weight piling back on. Some people even gain more weight than they lost in the first place.

了解这些风险很重要，因为许多服用这些药物的患者可能在余生都需要它们。就像放弃节食一样，停止服用高剂量的塞莫芦肽会导致体重反弹。有些人增重甚至比减重时还多。

Another preoccupation for policymakers is cost. In America the bill for Wegovy runs at around $1,300 a month; for Ozempic about $900. Judged by such prices, lifelong prescriptions look forbiddingly expensive. The longer view, however, is more encouraging. In time, companies may strike deals with governments and health providers to cover the whole population, ensuring high volumes in return for low prices. The prospect of profits is already luring competition and spurring innovation. Amgen, AstraZeneca and Pfizer are all working on rival drugs; Novo Nordisk has a full pipeline of follow-on drugs. Further ahead still, patents will expire, enabling the development of lower-priced generics.

政策制定者关注的另一个问题是成本。在美国，Wegovy每月的费用约为1300美元；Ozempic大约900美元。从这样的价格来判断，终身处方看起来贵得吓人。然而，从长远来看，情况更令人鼓舞。随着时间的推移，公司可能会与政府和医疗服务提供者达成协议，覆盖整个人口，确保以低价格换取高数量。利润前景已经在吸引竞争，刺激创新。安进(Amgen)、阿斯利康(AstraZeneca)和辉瑞(Pfizer)都在研发竞争对手的药物；Novo Nordisk有一个完整的后续药物流水线。再往后，专利将到期，从而使低价仿制药得以开发。

What to do in the meantime? Governments must ensure that those who most need the drugs get them, leaving those taking them for cosmetic purposes to pay out of their own pockets. The long-term effects must be carefully studied. States should keep pressing other anti-obesity measures, such as exercise, healthy eating and better food labelling, which may help prevent people from getting fat in the first place. But spare a moment to celebrate, too. These new drugs mean that the world’s fight against flab may eventually be won.

在此期间该做什么?政府必须确保那些最需要药物的人得到它们，让那些为了美容目的而服用药物的人自掏腰包。长期影响必须仔细研究。各国应继续推行其他反肥胖措施，如运动、健康饮食和更好的食品标签，这可能有助于从一开始就防止人们变胖。但也要抽出一点时间来庆祝一下。这些新药意味着全世界对抗肥胖的斗争可能最终取得胜利。