A study into parental smoking and childhood obesity has challenged previous notions by revealing that the links between the two are not confined to a specific socio-economic group.
The data shows a strong correlation between parents who smoke and their children's consumption of high calorie unhealthy foods and drinks, across social classes.
Using longitudinal data on 5,000 Australian children collected over a 10-year period, the research found those living with parents who smoke, on average, eat less healthy, higher calorie food such as fruit juice, sausages, fries, snacks, full fat milk products, and soft drinks.
Lead researcher Dr Preety Srivastava said the findings are a reminder that obesity - which continues to be a leading public health concern globally - is an issue across all classes and social groups.
"Australia has one of the highest rates of childhood obesity among rich nations, with data indicating one in four Australian children are overweight or obese in 2017-18," she said.
Poor taste leads to poor food choices
Preety Srivastava said it was important to understand that parental smoking had a greater potential impact than just the risks of passive smoke exposure. Another significant way that smoking affects children's health is through parents' role in modelling dietary behaviours to their kids.
"Previous studies show that compared to non-smokers, smokers have a higher preference for high energy and high fat foods due to the loss of taste sensitivity caused by nicotine and other chemicals found in cigarettes.
"In households where either or both parents smoke, children are exposed to more of these 'high flavour' foods possibly due to the altered taste preference of their parents."
Smoking doesn't discriminate
Although the bulk of evidence shows that low-socioeconomic families experience higher risks of obesity and smoking than other groups, the research found the link between parental smoking and childhood obesity to be prevalent across socio-economic classes.
"We separated the data into three socio-economic groups - lower, middle and upper - and found that all three equally demonstrated the link between parents who smoke and obesity in children.
"We did, however, find that mothers smoking behaviour could have a significantly greater negative impact on childhood obesity than fathers smoking behaviour.
"As they're often the primary caregivers of their children and handle household tasks such the food shopping and cooking, it is possible that mothers who smoke have a more significant influence on their children's diet."
Breaking the chain
The implications of these findings are far-reaching and emphasise the need for targeted public health interventions to curb parental smoking and promoting healthier diets for children.
"Our findings underscore the need for tobacco control measures that help parents quit smoking or reduce their tobacco use as doing so can have positive spillover effects on family health behaviours, including dietary choices and physical activity.
"Obesity can have negative emotional and social impacts on children, such as low self-esteem and increased rates of being bullied and socially excluded with further adverse consequences on academic performance and long-term employment opportunities.
"It is important policymakers, healthcare professionals, educators and parents collaborate to address the root causes of childhood obesity."
'The links between parental smoking and childhood obesity: data of the longitudinal study of Australian children' was published in BMC Public Health 24, 68 (2024) (DOI: 10.1186/s12889-023-17399-5). Authors: Preety Srivastava (RMIT University), Trong-Anh Trinh (Monash University), Karen T. Hallam (RMIT University), Leila Karimi (RMIT University) and Bruce Hollingsworth (Lancaster University).