Besides genetic factors, mother's weight can directly influence a child's body mass index (BMI) in adolescence, finds a new study.The study found that adolescents whose mothers do not stay physically active are likely to become overweight.On the other hand, their low weight can also affect them. "Parents have a major impact on their children's health and lifestyle. Behaviours that lead to obesity are easily transferred from parent to child," said Marit Naess, doctoral student at the Norwegian University of Science and Technology (NTNU) in Trondheim, Norway."If mom drops two to six kilos, this can be linked to lower BMI in the kids," added Kirsti Kvaloy, researcher from the varsity. However, there was no significant link if the father loses weight.It could be because mothers are still the ones who are primarily responsible for planning activities in the home and perhaps for food choices too, although this study did not examine these issues, the researchers stated.For the study, the team included 4,424 children and parents.Findings, published in the journal BMJ Open, showed that on average, BMI is lower in families with higher education compared to families with less education.Maternal weight reduction seems to wield greater influence on children's BMI in families with higher education.The mother-child link may often revolve around the mother wanting to lose weight. She makes small changes in her diet and habits that involve the whole family, the researchers said.