Children of the '90s: Grandfathers smoking habits might affect girls' weight - BBC News

The Children of the 90s research suggests that granddaughters of men who smoked before the age of 13, carry more body fat.

More than 14,000 people were included in the findings from the University of Bristol.

The study's lead author, professor Jean Golding, said no effects were observed in male descendants.

The Children of the 90s is a long-term health research project.

Previous research in 2014 found that if a father started smoking regularly before reaching puberty at 11 years old, then his sons, but not his daughters, carried more body fat than expected.

However, in the newly published study, the analysis was extended to earlier generations using recently collected data on the grandfathers and great-grandfathers of study participants.

"First, that before puberty, exposure of a boy to particular substances might have an effect on generations that follow him," Prof Golding said.

The findings showed higher body fat in females whose paternal grandfathers or great-grandfathers had started smoking before the age of 13 compared to those whose ancestors began smoking after that age.

The study's authors have said further research would be needed to confirm these observations.