The study explores how caloric restriction (CR) extends the lifespan of Caenorhabditis elegans (C. elegans). Researchers identified several genes, called "eat genes," whose mutations cause partial starvation by impairing the worm's feeding mechanism. Most eat mutations significantly increase lifespan, with eat-2 mutants living up to 50% longer than wild-type worms. These findings suggest that CR extends lifespan by reducing food intake, a mechanism distinct from that of dauer formation mutants. However, CR does not further extend the lifespan of clk-1 mutants, indicating that these genes may affect similar processes. The study also identified two distinct genetic mechanisms for lifespan extension in C. elegans: one involving dauer formation genes (daf-1, daf-2, daf-16, daf-28) and another involving genes affecting development and behavior (clk-1, clk-2, clk-3, gro-1). The eat-2 mutants' lifespan extension does not require DAF-16 activity, and eat-2; daf-2 double mutants live longer than daf-2 mutants, suggesting that CR and dauer mutations act through different pathways. The study also examined unc mutants, which have movement defects. Most unc mutants do not extend lifespan, except for unc-26, which may do so due to reduced food intake. This supports the idea that lifespan extension in eat mutants is primarily due to reduced food intake. The study found that eat-2 and clk-1 mutations may affect lifespan by influencing a common process, possibly related to metabolism. However, eat-2 mutants have distinct phenotypes compared to clk-1 mutants, suggesting that while they may share a common mechanism, they affect different aspects of metabolism. The study concludes that CR extends lifespan in C. elegans by reducing food intake, a mechanism distinct from that of dauer mutants. This finding has implications for understanding the genetic basis of aging in both worms and vertebrates.The study explores how caloric restriction (CR) extends the lifespan of Caenorhabditis elegans (C. elegans). Researchers identified several genes, called "eat genes," whose mutations cause partial starvation by impairing the worm's feeding mechanism. Most eat mutations significantly increase lifespan, with eat-2 mutants living up to 50% longer than wild-type worms. These findings suggest that CR extends lifespan by reducing food intake, a mechanism distinct from that of dauer formation mutants. However, CR does not further extend the lifespan of clk-1 mutants, indicating that these genes may affect similar processes. The study also identified two distinct genetic mechanisms for lifespan extension in C. elegans: one involving dauer formation genes (daf-1, daf-2, daf-16, daf-28) and another involving genes affecting development and behavior (clk-1, clk-2, clk-3, gro-1). The eat-2 mutants' lifespan extension does not require DAF-16 activity, and eat-2; daf-2 double mutants live longer than daf-2 mutants, suggesting that CR and dauer mutations act through different pathways. The study also examined unc mutants, which have movement defects. Most unc mutants do not extend lifespan, except for unc-26, which may do so due to reduced food intake. This supports the idea that lifespan extension in eat mutants is primarily due to reduced food intake. The study found that eat-2 and clk-1 mutations may affect lifespan by influencing a common process, possibly related to metabolism. However, eat-2 mutants have distinct phenotypes compared to clk-1 mutants, suggesting that while they may share a common mechanism, they affect different aspects of metabolism. The study concludes that CR extends lifespan in C. elegans by reducing food intake, a mechanism distinct from that of dauer mutants. This finding has implications for understanding the genetic basis of aging in both worms and vertebrates.