引言：人类能活多久？

人类对时间的追问，可以追溯到文明的黎明。从古埃及法老们执着于死后永生的宏大建筑，到中国秦始皇派遣徐福率童男童女出海寻仙；从《吉尔伽美什史诗》中英雄为追寻永生之草历尽艰险，到《庄子》中“彭祖以久特闻”的传说——长寿与永生，始终是人类最古老、最持久的梦想之一。然而，这个梦想从未像今天这样接近科学验证的现实边缘。当我们站在21世纪的今天，重新审视“人类能活多久”这一古老命题时，发现答案可能比任何时代的想象都更为复杂，也更为激动人心。本章作为全书的开篇，将带领读者从宏观视角审视人类寿命的历史演变与当代挑战，厘清生物学年龄与实际年龄的根本区别，预告本书将要覆盖的核心议题，并阐明科学探索如何逐步揭开寿命密码的神秘面纱。

The human quest to understand time traces back to the dawn of civilization. From the grand tombs of Egyptian pharaohs who yearned for eternal afterlife, to the legend of Qin Shi Huang sending Xu Fu on a perilous voyage to find the elixir of immortality; from the Epic of Gilgamesh where the hero undergoes perilous journeys in search of the plant of eternal youth, to Zhuangzi's account of Pengzu who "lived exceptionally long"—the pursuit of longevity and immortality has remained one of humanity's oldest and most enduring dreams. Yet this dream has never seemed closer to scientific validation than it does today. As we stand in the 21st century and re-examine the ancient question of "How long can humans live?", we discover that the answer may be far more complex and thrilling than any previous era could have imagined. This opening chapter will guide readers through a macro-level examination of the historical evolution and contemporary challenges of human lifespan, clarify the fundamental differences between biological age and chronological age, preview the core topics covered in this book, and illuminate how scientific exploration is gradually deciphering the mysterious code of longevity.

历史透视：人类寿命的漫长演变 / A Historical Perspective: The Long Evolution of Human Lifespan

要理解人类寿命的现在与未来，首先需要回溯其漫长的历史轨迹。人类寿命的演化并非线性上升，而是充满了波动与转折，反映了社会、经济、医疗和环境的综合影响。

To understand the present and future of human lifespan, we must first trace its long historical trajectory. The evolution of human lifespan has not been linear but filled with fluctuations and turning points, reflecting the combined influences of society, economy, healthcare, and environment.

在漫长的狩猎采集时代，人类的平均预期寿命（life expectancy）大约在30至40岁之间。这个数字听起来令人沮丧，但需要注意的是，这一平均值受到婴幼儿期高死亡率的强烈影响。在缺乏现代医学和卫生条件的时代，许多人在幼年时期便因感染、营养不良或意外而死亡。如果一个人幸运地度过了脆弱的童年期，其预期寿命可能会显著延长。人类学家对现存狩猎采集部落的研究表明，当排除婴幼儿死亡因素后，成人个体的存活率可以相当高。这暗示着，在生物学层面，人类可能已经具备了活到六七十年甚至更久的潜力，只是被高企的早期死亡人数拉低了平均值。

During the long epoch of hunting and gathering, the average life expectancy for humans was approximately 30-40 years. This figure sounds discouraging, but we must recognize that it was strongly influenced by high mortality rates during infancy and early childhood. In an era lacking modern medicine and sanitation, many individuals died young from infections, malnutrition, or accidents. If one successfully navigated the vulnerable childhood years, their life expectancy could extend considerably. Anthropological studies of contemporary hunter-gatherer societies suggest that after excluding infant and child deaths, adult survival rates could be remarkably high. This implies that at the biological level, humans may have possessed the potential to live to sixty, seventy years, or even longer, only to have this average dragged down by early mortality.

农业文明的到来带来了复杂的社会变化。稳定食物来源的获取使得人口增长成为可能，但同时也带来了新的健康挑战。密集型农业意味着人群聚集，这为传染病的传播创造了条件。此外，农业劳动的体力消耗、单一作物饮食带来的营养不均衡，以及社会不平等导致的健康差异，都是新的压力因素。考古学研究发现，从新石器时代到古典时期，普通人的寿命并没有显著提升——很多文明中，普通人的平均寿命仍然徘徊在30岁左右。值得注意的是，精英阶层往往能够获得更好的饮食和医疗条件，其寿命可能显著高于普通人。这种寿命的社会分层，在人类历史上屡见不鲜。

The advent of agricultural civilization brought complex social transformations. While stable food sources enabled population growth, they also introduced new health challenges. Intensive agriculture meant population concentration, creating conditions for infectious disease transmission. Additionally, the physical demands of agricultural labor, nutritional imbalances from reliance on single crops, and health disparities stemming from social inequality all represented new stressors. Archaeological research reveals that from the Neolithic era to classical antiquity, ordinary people's lifespans did not increase substantially—across many civilizations, average life expectancy remained around 30 years. Notably, elites often enjoyed better nutrition and medical care, potentially living significantly longer than commoners. This social stratification of longevity has recurred throughout human history.

工业革命标志着人类寿命史上的一个转折点。从大约1750年到1850年，西方国家的人口预期寿命从约30岁上升到约40岁。这一进步主要归功于公共卫生措施的改善——包括清洁饮水系统的建立、污水处理的改进，以及对传染病传播途径认识的加深。疫苗接种的普及也发挥了关键作用，天花疫苗的推广挽救了无数生命。进入20世纪，医学领域的一系列突破更是将人类寿命推向了新的高度。抗生素的发现、青霉素的批量生产、麻醉和外科手术技术的进步、癌症早期筛查和治疗的改善，以及慢性病管理的优化，共同将全球平均预期寿命从1900年的约31岁提升到了21世纪的超过70岁。这一百年间的进步，超过了过去数千年人类寿命提升的总和。

The Industrial Revolution marked a turning point in human longevity history. From approximately 1750 to 1850, population life expectancy in Western nations rose from about 30 to 40 years. This progress was primarily attributable to improvements in public health measures—including the establishment of clean water systems, sewage treatment improvements, and deeper understanding of infectious disease transmission pathways. The spread of vaccination also played a critical role, with smallpox vaccination saving countless lives. Entering the 20th century, a series of medical breakthroughs pushed human lifespan to new heights. The discovery of antibiotics, mass production of penicillin, advances in anesthesia and surgical techniques, improvements in cancer screening and treatment, and optimization of chronic disease management collectively elevated global average life expectancy from approximately 31 years in 1900 to over 70 years in the 21st century. This progress in a single century exceeded the total lifespan improvement achieved throughout the previous several millennia.

中国的寿命变迁同样令人瞩目。1949年新中国成立时，人均预期寿命仅有约44岁，这与当时的经济社会发展水平和医疗卫生条件密切相关。改革开放以来，随着经济的快速发展和医疗体系的完善，中国人的预期寿命显著延长。根据世界银行数据，2020年中国人的平均预期寿命已达到约77岁，与许多发达国家不相上下。这一成就反映了中国在公共卫生、疾病防控、医疗保障等方面取得的全面进步，也彰显了社会发展对人类寿命的深远影响。

China's lifespan transformation has been equally remarkable. When the People's Republic of China was founded in 1949, average life expectancy was only approximately 44 years, closely related to the economic development level and healthcare conditions at that time. Since the reform and opening-up period, with rapid economic development and improvements in the medical system, Chinese life expectancy has significantly extended. According to World Bank data, by 2020, China's average life expectancy had reached approximately 77 years, comparable to many developed nations. This achievement reflects comprehensive progress in public health, disease prevention and control, and medical security in China, demonstrating the profound impact of social development on human longevity.

超越平均值：理解寿命的多重维度 / Beyond the Average: Understanding the Multiple Dimensions of Lifespan

然而，当我们讨论“人类能活多久”这一问题时，单纯的平均预期寿命并不能给出完整答案。寿命研究中有几个关键概念需要厘清，它们将帮助我们更深入地理解衰老的本质与极限。

However, when discussing the question of "How long can humans live?", average life expectancy alone cannot provide a complete answer. Several key concepts in longevity research require clarification—they will help us more deeply understand the nature and limits of aging.

平均预期寿命（Life Expectancy at Birth）是指某一年出生的婴儿预期能够存活的平均年数。这是一个统计学概念，反映的是特定时期、特定地区人口的整体健康状况和死亡模式。2023年，全球平均预期寿命约为73岁，而日本、香港、瑞士等长寿地区则超过了83岁。这些数字告诉我们的是群体层面的统计特征，而非个体的生物学极限。

Life expectancy at birth refers to the average number of years a baby born in a given year can expect to live. This is a statistical concept reflecting the overall health status and mortality patterns of a specific population at a specific time and place. In 2023, global average life expectancy was approximately 73 years, while longevity regions like Japan, Hong Kong, and Switzerland exceeded 83 years. These figures tell us about statistical characteristics at the population level, not individual biological limits.

最长寿命（Maximum Lifespan）则是另一个概念，它指的是某个物种中已知最长寿个体的年龄。对于人类而言，有可靠记录的最长寿命来自法国女性让娜·卡尔芒（Jeanne Calment），她于1997年去世，享年122岁零164天。卡尔芒的案例之所以重要，不仅因为她的长寿本身，更因为她的生活方式——她直到晚年都保持着相对活跃的状态，直到115岁还能骑自行车。这种“健康”与“长寿”并存的模式，为我们理解衰老的本质提供了重要线索。

**Maximum lifesp