(HealthDay News) -- For a certain kind of worm, the sweet life may also be the short life.

New research suggests that added sugar in their diet robs the creatures of 20 percent of their life span.

It's unclear what the findings mean for humans, but they raise questions about the impact of diets high in sugar, according to the study authors, who report their findings in the November issue of the journal Cell Metabolism.

In the study, researchers added a small amount of glucose -- sugar -- to the diet of worms known as C. elegans. The worms normally eat bacteria.

The worms had shorter lives, apparently because of the sugar's effect on the worms' insulin signals, according to the report.

One of the researchers, Cynthia Kenyon of the University of California at San Francisco, said the worms and people are actually similar in the way their bodies handle insulin.

"In the early '90s, we discovered mutations that could double the normal life span of worms," Kenyon said in a news release from the journal's publisher. Those mutations involved internal signals regarding insulin, she explained.

The researchers noted that although the research is in its early stages, it's possible that a low-glycemic index -- one that doesn't quickly boost blood-sugar levels -- could boost longevity.

Scientists are already at work on related research, trying to understand how tightly restricted diets -- in which animals eat much less than they normally would -- helps them live longer.

Humans could conceivably try to do the same thing, but it's impractical for many people to eat much less than their bodies tell them they should.

Meanwhile, as a result of her work, Kenyon has adopted a low-carb diet, giving up most starches and desserts.

More information

For more on low-carb diets, see the American Academy of Family Physicians.