Introduction:
Healthy weight adults who were overweight children have nearly identical cardiometabolic profiles to those who were healthy weight children, but few overweight children deviate from an obese trajectory. Understanding why some diverge could provide novel insights for public health interventions targeting childhood overweight/obesity ‘resolution’.
Methods:
Data were from a qualitative sub-study (2016; 38-46 years) of participants involved in the first (2004-6), second (2009-11) and third (2014-16) follow-ups of 8,498 children (7-15 years) from the 1985 Australian Schools Health and Fitness Survey. Using body mass index (BMI) z-scores, trajectory-based group modelling identified five trajectories: stable/low, stable/normal, high/decreasing, normal/increasing and high/increasing. Semi-structured interviews were conducted with six to twelve participants from each trajectory (n=50; 60% women) and thematically analysed exploring individual, social and environmental influences on weight, eating and physical activity since childhood.
Major findings:
The legacy of parental influences during childhood on lifestyle behaviours in adulthood was a strong theme discussed by the stable and high/decreasing groups (e.g. “mum did a great job setting me up”), persisting despite phases of unhealthy behaviours. In contrast, the legacy effect was weaker in the normal/increasing and high/increasing BMI groups (e.g. parents had ‘a little bit’ of influence). Some participants in the stable and decreasing groups suggested that their childhood or parents’ lifestyle was not healthy, prompting them to adopt a healthier lifestyle (e.g. “I didn’t smoke and I don’t drink really, and my mum did all those things and never did anything physical”).
Concluding statement:
This novel mixed-methods study is the first to link a lasting impact of parents’ lifestyle behaviours to divergent BMI trajectories from childhood to adulthood. This work deepens understandings of the long-term influence of childhood experiences on adult health, and provides direction for further quantitative exploration of divergent BMI trajectories.