Why people gain weight as they get older

为什么随着年龄的增加，体重也会增长？

上海译锐翻译   2019-9-12    09:26a.m.

Many people struggle to keep their weight in check as they get older. Now new research at Karolinska Institutet in Sweden has uncovered why that is: Lipid turnover in the fat tissue decreases during ageing and makes it easier to gain weight, even if we don't eat more or exercise less than before. The study is published in the journal Nature Medicine.

随着年纪渐长，许多人都在试图控制自己的体重。如今，瑞典卡罗林斯卡医学院的一项新研究发现了这一现象背后的原因：脂肪细胞中的脂代谢会随着年龄的增加而有所减少，因此即使我们没有比之前吃更多或锻炼更少，体重也还是会轻而易举地蹭蹭上涨。研究结果发表在期刊《自然医学》中。

The scientists studied the fat cells in 54 men and women over an average period of 13 years. In that time, all subjects, regardless of whether they gained or lost weight, showed decreases in lipid turnover in the fat tissue, that is the rate at which lipid (or fat) in the fat cells is removed and stored. Those who didn't compensate for that by eating less calories gained weight by an average of 20 percent, according to the study which was done in collaboration with researchers at Uppsala University in Sweden and University of Lyon in France.

科学家们在平均13年的时间内研究了54位男性和女性的脂肪细胞。在这段时间内，所有的受试对象，无论体重增加还是减少，都出现脂肪细胞内脂代谢减少的情况。脂代谢是指脂质（或脂肪）在脂肪细胞中被移除并储存的速度。根据瑞典乌普萨拉大学和法国里昂大学的研究者们所共同开展的一项研究，那些未通过减少摄入卡路里而弥补脂代谢减少的人平均会增重20%。

The researchers also examined lipid turnover in 41 women who underwent bariatric surgery and how the lipid turnover rate affected their ability to keep the weight off four to seven years after surgery. The result showed that only those who had a low rate before the surgery managed to increase their lipid turnover and maintain their weight loss. The researchers believe these people may have had more room to increase their lipid turnover than those who already had a high-level pre-surgery.

研究者们还查看了41位做过减肥手术的女性的脂代谢以及他们的脂代谢是如何在术后4到7年的时间内对维持体重产生影响的。研究结果表明，只有那些在外科手术前脂代谢偏低并在手术后设法增加代谢的人成功保持了体重。研究人员相信，与在术前脂代谢已经处于较高水平的人相比，这些人可能有更大的可能性来增加其脂代谢。

"The results indicate for the first time that processes in our fat tissue regulate changes in body weight during ageing in a way that is independent of other factors," says Peter Arner, professor at the Department of Medicine in Huddinge at Karolinska Institutet and one of the study's main authors. "This could open up new ways to treat obesity."

“结果首次表明，脂肪细胞中的处理过程会在变老过程中对体重变化进行调节，这一调节不会受到其他任何因素的影响”，Peter Arner，卡罗林斯卡医学院呼丁格医学系教授、研究项目主要作者之一表示。“这为我们治疗肥胖打开了新的大门。”

Prior studies have shown that one way to speed up the lipid turnover in the fat tissue is to exercise more. This new research supports that notion and further indicates that the long-term result of weight-loss surgery would improve if combined with increased physical activity.

之前的研究已经表明，加速脂肪细胞中脂代谢的一个办法就是加大训练量。这项新研究为这一观念提供了支持并进一步表明，如果能够与增加体育锻炼相结合，减肥手术会有更好的持久效果。

"Obesity and obesity-related diseases have become a global problem," says Kirsty Spalding, senior researcher at the Department of Cell and Molecular Biology at Karolinska Institutet and another of the study's main authors. "Understanding lipid dynamics and what regulates the size of the fat mass in humans has never been more relevant."

Kirsty Spalding，卡罗林斯卡医学院细胞和分子生物学系高级研究员、本研究项目另一位主要作者表示：“肥胖和肥胖有关的疾病已成为全球性的问题。了解脂质的动力学和对人体脂肪大小产生影响的因素从未如此重要。”