Don't pay too much attention to the buzz around extending your life by eating less: New research with fruit flies suggests that, contrary to previous reports, diet restriction may not increase lifespan.

Recent research has shown that eating fewer calories lengthened the lives of fruit flies and mice. Earlier this month, a study in Science found that to be true for rhesus monkeys, moving the work closer to humans.

In the current study, reported in the journal PLoS-Biology, Dr. David S. Schneider and Dr. Janelle S. Ayres, from Stanford University, California, examined how loss of appetite, which is brought on by most infections, affects the ability of Drosophila to fight various bugs.

Eating fewer calories had a "complicated" effect on the immune system, Schneider told Reuters Health. It helped fight off some bugs, but made the flies more vulnerable to others.

The results indicate that diet restriction is not a "panacea" for longer survival, Dr. Schneider pointed out. Nonetheless, further research is needed to determine if these findings from fruit flies also extend to other animals, including humans, he added.