Scientists have known for decades that restricted dietary intake can increase the lifespan of many species, but the mechanism that causes this is not understood. Short-lived organisms like the fruit fly, Drosophila melanogaster, are studied to help unravel this mystery, and the knowledge gained could have important implications for human health.
In a paper to be published in Science, the journal of the American Association for the Advancement of Science, a group of researchers from Baylor College of Medicine in Houston, New Mexico State University in Las Cruces and the University of Houston report that exposure to food odors can modulate lifespan and partially reverse the longevity-extending effects of dietary restriction in fruit flies.
"Not only can they not have their cake ?they can't smell their cake" without shortening their lifespans, said Wayne Van Voorhees, a faculty member in the Molecular Biology Program at New Mexico State University and a member of the research collaboration.
The researchers, led by Scott Pletcher of the Huffington Center on Aging at Baylor, measured the lifespans of different strains of fruit flies in the presence and absence of food odors ?specifically live yeast, which is an important component of the flies' diets. Exposure to food odors reduced lifespan in flies that had been subjected to dietary restriction. The reductions ranged from 6 percent to 18 percent ?not as much reduction as actual consumption of more food caused, but significant enough to show that food odors have a modulating effect on lifespan.
The researchers also studied genetically altered strains of fruit flies to determine whether loss of olfactory function ?the sense of smell ?had an effect on lifespan. Th
Source:New Mexico State University