撰文丨王聪 编辑丨王多鱼 排版丨水成文 饮食限制 （ dietary restriction，DR ） ，是一类限制热量摄入但不造成营养不良的饮食方案，包括禁食、模拟禁食、低升糖指数饮食等，可延长哺乳动物寿命， 并延 缓包括癌症在内的年龄相关疾病的发生，但其背后的具体机制尚不完全清楚。 2025 年 12 月 9 日，美国 范安德研究中心的研究人员在 Nature 子刊 Nature Metabolism 上发表了题为： Dietary restriction reprograms CD8 + T cell fate to enhance anti-tumour immunity and immunotherapy responses 的研究论文。 该研究表明， 饮食限制 引起的 酮体代谢变化 （产生更多的 β-羟基丁酸 ） 可重编程肿瘤微环境中的 CD8 + T 细胞命运和功能，从而增强抗肿瘤免疫和免疫治疗 响应。 那么，饮食限制是如何实现这一神奇转变的呢？答案在于—— 酮体代谢 。 当身体处于饮食限制状态时，肝脏会产生更多的 β-羟基丁酸 （βOHB） 等酮体。研究团队发现，这些酮体能够作为 CD8 + ...

Core Viewpoint - The article discusses the implications of recent research on calorie restriction (CR) and intermittent fasting (IF) on health and longevity, highlighting the potential trade-offs between lifespan extension and overall health [9][11][19]. Summary by Sections Research Findings - A study conducted by Calico Life Sciences in collaboration with other institutions revealed that calorie restriction can extend lifespan significantly, with a 40% CR group showing a lifespan increase of 36.3% compared to ad libitum (AL) groups [13][15]. - Intermittent fasting (IF) showed some benefits in lifespan extension, but its effects were less pronounced than those of calorie restriction, with the 1D and 2D fasting groups showing only slight increases in lifespan [13][19]. Health Implications - While CR can extend lifespan, it may lead to adverse health effects, such as reduced immune function and weight loss, which could increase infection risk [15][19]. - The study found that IF could also have health risks, such as increased red blood cell distribution width (RDW), which is associated with aging and mortality [16][19]. Weight and Longevity Paradox - The research highlighted a paradox where lower body weight does not necessarily correlate with longer lifespan, suggesting that maintaining an appropriate weight and fat content is crucial for longevity [17][19]. - Genetic factors were found to play a significant role in lifespan variation, with 23.6% of lifespan variation in younger mice explained by genetics, compared to only 7.4% by diet [17][19]. Conclusion - The findings suggest that while dietary restrictions can extend lifespan, they may compromise health, indicating a need for caution regarding extreme dieting methods [19]. Further research is required to understand the specific impacts of these dietary practices on human longevity [19].