Male and female school age children with an overweight or obese mother have a higher chance of being overweight when compared to the influence of the weight of their father, according to the study of almost two decades worth of data.
When both parents are overweight or obese, the data suggested that the probability of male children being overweight or obese is higher than female children.
The study analysed a dataset from the Health Survey for England using the body mass index (BMI) chart to study over 14,000 families between 1995 and 2009.
Environmental influences were also considered including parents’ age, their mental health, smoking or alcohol consumption, socio-economic status, employment status and ethnicity.
“The transmission of obesity by both parents, the individual father or the individual mother, depend crucially upon the gender of the child,” said Professor Jofre-Bonet, who led the study.
“The transmission seems to be stronger for maternal than paternal overweight,” she continued.
Maternal influences stronger than paternal
Estimates made by the International Association for the Study of Obesity indicate that the UK has some of the highest rates in Europe of overweight and obese children aged 5-17 years old.
The results are consistent with the view that if parents are overweight or obese, there is a higher chance that their children will be overweight too. However, the study found that the unique effects of individual parents depended on the age and gender of the child.
“Males in their teens with both parents overweight or obese face an increased probability of being overweight,” said Professor Jofre-Bonet.
She continued: “In contrast, if only their father is overweight and they are in primary school instead, they have an increased probability of being overweight but have lower chances of being obese than a pre-school male child.”
“Having an obese mother alone increases the likelihood of a pre-school male child being obese.”
Comparing that to females, Professor Jofre-Bonet said: “We find that among female children, the association of the child’s overweight or obesity with her mother’s is larger than it is with her father’s weight.
“School-age female children with an overweight or obese mother have an increased likelihood of being overweight or obese.
“Female children in their teens with obese mothers are also more likely to be overweight or obese.”
Transmission of overweight stronger in older parents but weaker in single children
The study also found that while mothers over the age of 30 at the time of birth are less likely to have overweight and obese children, if they themselves are obese, they are more likely to have overweight children.
When both parents are obese, the likelihood of the children being overweight or obese increases with the age difference between the parents and child.
Despite popular beliefs, the study found no evidence to suggest that being a single child has any statistical impact on the transmission of being overweight.
The only exception being when both parents are obese – where the probability of a single child being overweight increases.
“The implications of the study are important as they suggest special attention is needed for families where both parents are overweight.” said Professor Jofre-Bonet.
She continued saying: “Health policy interventions should place special attention to school-age female children, particularly when their mother is obese.
“We find that lower income parents are more at risk of being overweight, and so are their children. Hence, interventions should focus more on lower income families to be more effective.”
The full paper: ‘Is the Intergenerational Transmission of Overweight ‘Gender Assortative?,’ will be published in the Journal for Economics and Human Biology.