Abstract
The increase in the prevalence of overweight and its negative consequences is of great concern. Overweight is now seen in younger populations, and, as evidence associates overweight with rapid weight gain in early life, and there is a lack of long-term success with treatment, a preventative approach may be a more effective. Specific modifiable factors associated with the risk of developing overweight have been identified, but as yet there are few prevention studies looking at the effect of intervention from birth on these modifiable factors.
The Prevention of Overweight in Infancy (POI) study is a randomised controlled trial run by the Department of Women’s and Children’s Health at the University of Otago, in conjunction with the Departments of Medicine, Human Nutrition, and Preventive and Social Medicine. Its aim is to determine whether extra support around sleeping, eating and physical activity during infancy and toddlerhood can reduce the rate of excessive weight gain in the first two years of life. Eight hundred and four Dunedin mothers were randomised to one of four groups (control; sleep intervention; food, activity and breastfeeding intervention; or a combination group) before their infant was born.
This thesis uses data collected as part of the POI study, to examine the effect of one part of the intervention (the 7-month session) on dietary outcomes at 12 months of age. The specific aim of this thesis is to assess whether a targeted dietary intervention at 7 months of age can affect eating behaviours, and overall dietary patterns at 12 months of age as assessed by a questionnaire and FFQ.
Principal component analysis of the FFQ data collected at 12 months revealed five distinct patterns: Healthy home-prepared, Less healthy, Older child, Less healthy infant and Healthy infant. There were no differences in diet pattern scores between the intervention groups. The patterns were, however, associated with socio-demographic variables. Education was associated with the first four dietary patterns, with higher education associated with higher Healthy home-prepared scores and lower Less healthy and Older child scores. Conversely, higher education was associated with higher Less healthy infant scores.
Greater parity was associated with higher Less healthy and Older child food pattern scores. Marital status was also associated with Less healthy and Older child food patterns scores with those who were single having higher scores in these food patterns.
Our intervention was effective in encouraging mothers to offer new foods multiple times. Being in the Combination group (who received both sleep and food and activity interventions) increased the likelihood of eating meals as a family more frequently, and of offering fruit more frequently. The single session with families when their infant was 7-months old was not, however, effective in influencing the number of times that vegetables, treat foods or sugary drinks were offered, or the use of a cup not a bottle at 12 months of age.
In conclusion, a session targeting specific food behaviours at 7 months of age increased specific behaviours of offering new foods multiple times, offerings of fruit, and the frequency of family meals, but did not affect dietary patterns at 12 months of age.