高蛋白饮食和寿命长短有关系吗

Research shows that a diet high in protein and low in carbohydrates can help shed pounds and normalize blood-glucose levels, improvements that lower the risk of diabetes and cardiovascular disease.
研究表明，含有高蛋白、低碳水化合物的饮食有助于减肥并能使血糖水平恢复正常，而血糖水平得到改善能降低糖尿病和心血管疾病的患病风险。

But will you live longer on a high-protein, low-carb diet? Two studies in the current edition of the scientific journal Cell Metabolism suggest the opposite. One involved an experiment conducted on mice, the other an 18-year study of humans who had divulged their dietary habits. Both studies found a strong association between longevity and a low-protein, high-carbohydrate diet, although the human study bore a twist: Beyond age 65, higher protein levels appeared to promote longevity.
但你会因为高蛋白、低碳饮食而活得更久吗？科学期刊《细胞代谢》(Cell Metabolism)本期上的两项研究认为答案是否定的。其中一则研究涉及对老鼠进行的一项试验，另一则项则对那些暴露自己饮食习惯的人进行了长达18年的研究。尽管针对人类进行的研究与最终的结论有些出入，即过了65岁以后，更高的蛋白水平似乎会延年益寿。但前述两项研究均发现：在长寿与高蛋白、低碳水化合物的饮食习惯之间存在着一种强烈的关联。

'Those high-protein diets were developed with a shortsighted vision,' said Valter D. Longo, a University of Southern California professor of gerontology and biological sciences and the lead author of the human study. 'On a high-protein, high-fat diet you can lose weight, but in the long run you may be hurting yourself.'
南加州大学(University of Southern California)老年医学和生物科学教授、上述人类研究的首席作者瓦尔特・D・隆戈(Valter D. Longo)说：“那些高蛋白饮食的发展伴随着一种短视现象。坚持高蛋白、健康高脂的饮食习惯，你是可以减肥，但长远来看，你现在的所在所为可能正在伤害你自己。”

These studies are anything but definitive, showing only associations derived from highly limited evidence. But in gerontology, the influence of protein consumption on longevity is a hot topic. Last year, the American Federation for Aging Research hosted a symposium on 'Optimal Protein Intake for Older Adults,' featuring a panel of scientists from academia and industry. No concrete answers emerged, except perhaps that protein consumption influences health in ways that are complex.
这些研究目前均无定论，仅仅显示出了一些关联性，这些关联性还是从非常有限的证据中提炼出来的。但在老年医学中，蛋白质摄取对寿命的影响是一个热门话题。去年，美国联邦老化研究所(American Federation for Aging Research)举办了一场有关“老年人最佳蛋白摄取量”的研讨会，有一组来自学界和业界的科学家出席了会议。对于前述问题，大家尚未得出具体的答案，或许只有这样一个结论：蛋白质摄取量会通过复杂的方式影响健康。

'High protein diets may be effective to lose weight rapidly,' said Elena Volpi, a professor of geriatrics at the University of Texas Medical Branch in Galveston. 'But very high protein diets may also be harmful.'
德克萨斯大学加尔维斯顿医学分部(University of Texas Medical Branch in Galveston)老年病学教授埃琳娜・沃尔皮(Elena Volpi)说：“高蛋白饮食对快速减肥可能会有效，但特别高的蛋白饮食可能也会有害。”

In the human study, those consuming high levels of plant-based protein had a threefold increase in cancer mortality but no higher rate of overall mortality. That suggests, as other research has shown, that there may be benefits from minimizing consumption of animal-based protein. 'These results indicate that respondents ages 50 to 65 consuming moderate to high levels of animal protein display a major increase in the risks for overall and cancer mortality,' the researchers concluded.
在上述针对人类的研究中，那些摄取高植物蛋白的人群癌症死亡率增加了三倍，但并未出现更高的总体死亡率。那表明──也正如其他研究所示──将动物蛋白摄入量最小化可能会有所裨益。研究人员得出结论称：“这些结果表明，那些食用中到高水平动物蛋白、年龄在50到65岁的受访者在总体死亡率和癌症死亡率方面的风险大幅增加。”

For subjects 66 and older, the opposite proved true: Higher protein consumption was associated with greater survival. Gerontologists say this makes sense, because the ability to absorb protein appears to diminish in the aging body, requiring perhaps greater consumption.
而在那些年龄为66岁及以上的受访者身上，事实证明情况正好相反：更高的蛋白质摄取量与更大的生存机会息息相关。老年病学者称，这个完全说得通，因为在衰老的身体内，吸收蛋白的能力似乎会减弱，这就可能需要更高的摄取量。

Even then, though, the takeaway is somewhat complicated. Americans tend to consume the bulk of their protein at dinner, and the body isn't always able to process an entire day's worth in one sitting, said Dr. Volpi, who wasn't involved in either study. 'It appears you can better use the protein you need if you distribute it across three meals, especially if you are a senior,' she said.
然而即便如此，有关蛋白质的摄取问题还是有些复杂。沃尔皮博士说，美国人倾向于在晚餐时进食他们一天中的大部分蛋白质，而人体并非总能一口气消化掉一整天的营养。她还说：“如果你能将蛋白质的摄取任务分配到一日三餐中，你似乎就能更好地利用所需的蛋白质，尤其当你是位老年人时，情况更是如此。”沃尔皮并未参与到上述的任何研究中。