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Life Extension May Add Just Bad Time

Living longer doesn’t necessarily mean living better. That’s the lesson from the tiny roundworm called C. elegans, long a workhorse in basic biology lab work. The research is in the Proceedings¹ of the National Academy of Sciences.

长寿并不一定意味着活得更好。这是从一种被称为“线虫”的小蛔虫身上吸取的教训，而它正是基础生物学实验室工作的一个主力。该研究刊发于《美国国家科学院院刊》。

In the study, thousands of normal C. elegans competed against strains that live days or weeks longer than their brethren, because of factors like genetic² mutations or very low-calorie diets.

在研究中，成千上万的正常线虫跟那些比它们多活几天或几周的菌株同胞做比较，而 “较长寿”的菌株之所以活得更长是因为类似基因突变或非常低热量的饮食这些因素。

But a battery of tests to see how the all older worms moved or responded to stress revealed some hard truths: increased life span did not usually come with a prolonged period of health and strength. Indeed, the “good times” for each of the worms was roughly the same, regardless of their overall life span. In other words, the longer-living worms spent a greater proportion of their lives in a diminished state—with less mobility³ and stress resistance.

但关于“长寿蛔虫”如何继续生存及应对压力的一连串测试，则显示出了一些残酷的事实：延长寿命通常并不意味着也延长了健康和力量。事实上，无论整体寿命长短，所有蠕虫的“壮年” 时期大致是相同的。换句话说，较长寿的蛔虫花了更多时间生活在“衰弱”的状态——拥有较弱的流动性和抗逆性。

Aging worms are not aging humans. But if the findings do extend to people, then life-extension efforts, such as calorie restriction⁴, may not shake out to a better old age, just more years of frailty⁵. With associated healthcare cost increases and quality of life decreases. The researchers suggest that it’s time to start thinking about what they call “healthspan”—and maximizing “healthspan,” rather than just tacking⁶ on years of poor quality.

衰老的蛔虫并非衰老的人类。但如果该研究结果真能延伸到人类身上，那么诸如限制热量摄入这种延年益寿之举，可能并不会带来一个更好的晚年，而只是徒增了几年的衰弱。与此同时，医疗成本增加了而生活质量却下降了。研究人员认为，是时候思考他们称之为“健康寿命”——及“健康寿命”最大化这一课题了，而不是仅仅考虑徒增几年“衰弱”的寿命。