London, Feb 6 (IANS): If new research in male fruit flies holds up, eating lima beans might help men live longer.

The researchers found that administering an oral dose of prunetin, found in lima beans, to male fruit flies extends lifespan, increases fitness levels, and improves their glucose balance. 

"Our study provides novel insights into plant bioactive research and suggests a potential to combat ageing comparatively simple by the intake of a plant bioactive," said one of the researchers Anika Wagner from University of Kiel in Germany. 

"Further studies in mammalian species/humans are needed to validate initial data which were generated in the model organism Drosophila melanogaster," Wagner noted.

To make their discovery, scientists separated fruit flies according to sex prior to the start of the experimental treatment to compare prunetin-mediated effects on both males and females. 

The flies were then chronically administered either a prunetin-containing diet or a prunetin-free control diet. 

The flies were monitored every other day, and dead flies were counted. 

The researchers found that prunetin-fed male flies lived longer than those receiving the control diet. 

To evaluate their health state / fitness, the flies were coerced to climb up in a transparent tube and the distance which they could overcome in a defined time period was calculated.

This effect was not found in females. 

As females are long-lived compared with their male counterparts, prunetin apparently “feminises” male flies via its estrogenicity, the researchers said.