A study of fruit flies that have had their scent genes mutated shows that they live up to 30% longer than normal flies. Quick, buy some noseplugs!
The experiment mutated flies so they didn't have a gene that allowed them to smell carbon dioxide, which is how they detect the presence of yeast. It caused them to live longer as well as display strong health indicators.
What happened? It may have tricked them into thinking there was no food around, so their metabolism slowed down to conserve their nutritional supplies.
So basically, stop smelling delicious food all the time and your body won't expect it. Very clever! Now who wants to try it out? [PopSci]