Cell Metab. 10, 379–391 (2009)

Nematode worms fed on a diet spiked with glucose die about 20% earlier than those consuming just the bacterium Escherichia coli.

Cynthia Kenyon and her colleagues at the University of California, San Francisco, found that dietary glucose inhibits the DAF-16 and HSF-1 proteins, which are known to lengthen nematode lifespan. This in turn lowers the activity of the gene aqp-1, which codes for a glycerol channel, suggesting that glucose shortens lifespan by affecting glycerol metabolism.

Worms consuming glycerol also died earlier. The authors think that the worms metabolize glucose into glycerol, which then initiates life-shortening processes.