VOA健康报道2024--Has Human Life Expectancy Reached Its Limit?

Has Human Life Expectancy¹ Reached Its Limit?

A new study says humanity is hitting the upper limit of life expectancy.

Developments in medical technology and genetic² research are not leading to major increases in lifespan overall, the researchers said.

The study was published recently in Nature Aging.

"We have to recognize there's a limit" and possibly change ideas about when people should retire and how much money they will need to live out their lives, said S. Jay Olshansky of the University of Illinois-Chicago. Olshansky was the lead writer of the study.

Mark Hayward of the University of Texas was not involved in the study. However, he called it "a valuable addition to the mortality literature."

"We are reaching a plateau" in life expectancy, he said.

It is always possible that some new development could push survival to greater lengths, "but we don't have that now," Hayward said.

What is life expectancy?

Life expectancy is an estimate of the average number of years a baby born in a particular year might expect to live. The measurement assumes death rates at the time of birth do not change.

Life expectancy is one of the world's most important health measures. Still the life expectancy measurement has problems. For example, life expectancy is an estimate that cannot include new developments or changes that might affect the length of people's lives.

These unknown developments could include pandemics or new treatments for diseases.

In the recent study, Olshansky and other researchers followed life expectancy estimates for the years 1990 to 2019. They took information from a database administered by the Max Planck Institute for Demographic Research.

The researchers paid special attention to eight of the places in the world where people live the longest: Australia, France, Hong Kong, Italy, Japan, South Korea, Spain and Switzerland.

The United States does not rank in the top 40, but it was included in the study because the researchers live in the U.S. Also, some experts have made estimates that life expectancy in the U.S. would increase greatly in the 2000s, Olshansky said.

Who lives the longest?

Women continue to live longer than men. Female life expectancy improvements are still happening - but at a slower rate, the researchers found. In 1990, the average amount of improvement was about 2.5 years every 10 years. In the 2010s, it was 1.5 years - but almost zero in the United States.

Life expectancy measurements in the U.S. are more difficult. The country is affected³ by a number of causes of early death. Examples include drug overdoses, shootings, weight problems and uneven⁴ health care services.

But in one calculation, the researchers estimated what would happen in all nine places if all deaths before age 50 were prevented. The increase at best was still only 1.5 years, Olshansky said.

The study suggests that there is a limit to how long most people live, and we have almost hit it, Olshansky said.

"We're squeezing less and less life out of these life-extending technologies. And the reason is, aging gets in the way," he said.

It may seem common to hear of a person living to 100. Former U.S. President Jimmy Carter, for example, recently celebrated⁵ his 100th birthday.

In 2019, a little over two percent of Americans made it to 100, compared to about five percent in Japan and nine percent in Hong Kong, Olshansky said.

It is likely that the number of people who reach 100 will grow in the years ahead, experts say, but that is because of population growth. The percentage of people hitting 100 will remain limited, likely with fewer than 15 percent of women and 5 percent of men making it that long in most countries, Olshansky said.

Words in This Story

mortality -- n. the death of large numbers of people

literature -- n. the body of writings on a particular subject

plateau -- n. a relatively⁶ stable level, period, or condition

assume -- v. to take as granted or true

extend -- v. to stretch out to fullest length

1 expectancy   

n.期望，预期，（根据概率统计求得）预期数额

参考例句：

• Japanese people have a very high life expectancy.日本人的平均寿命非常长。
• The atomosphere of tense expectancy sobered everyone.这种期望的紧张气氛使每个人变得严肃起来。

2 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

3 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

4 uneven   

adj.不平坦的，不规则的，不均匀的

参考例句：

• The sidewalk is very uneven—be careful where you walk.这人行道凹凸不平—走路时请小心。
• The country was noted for its uneven distribution of land resources.这个国家以土地资源分布不均匀出名。

5 celebrated   

adj.有名的，声誉卓著的

参考例句：

• He was soon one of the most celebrated young painters in England.不久他就成了英格兰最负盛名的年轻画家之一。
• The celebrated violinist was mobbed by the audience.观众团团围住了这位著名的小提琴演奏家。

6 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。