NEW YORK (AP) -- Here's some good news for older dads. A new study hints that your children and even your grandchildren may get a health benefit because of your age when you became a dad.

That's based on research into something called telomeres, which are the tips at the end of the chromosomes. Some scientists believe telomeres hold secrets into longevity and aging and that longer telomeres may mean healthier, longer lives. That hasn't been proven.

Before the new study, scientists knew that the older a man is when he becomes a father, the longer the telomeres his children tend to have. The new research finds that even extends to grandchildren. So the older your father's father was when he had your father, the longer your chromosomes tend to be. There's no effect from your mother's father.

Researchers said their result does not argue for delaying fatherhood, though. That's because older dads also tend to pass along some genetic mutations that might be harmful.

The work is published in the Proceedings of the National Academy of Sciences.