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PEDIATRIC ORIGINAL ARTICLE
Fast food, other food choices and body mass index
in teenagers in the United Kingdom (ALSPAC):
a structural equation modelling approach
LK Fraser1, KL Edwards2, JE Cade3 and GP Clarke1
School of Geography, University of Leeds, Leeds, UK; 2Division of Biostatistics, University of Leeds, Leeds, UK and 3Nutritional Epidemiology Group, University of Leeds, Leeds, UK
Objective: To assess the association between the consumption of fast food (FF) and body mass index (BMI) of teenagers in a large UK birth cohort.
Methods: A structural equation modelling (SEM) approach was chosen to allow direct statistical testing of a theoretical model. SEM is a combination of confirmatory factor and path analysis, which allows for the inclusion of latent (unmeasured) variables. This approach was used to build two models: the effect of FF outlet visits and food choices and the effect of FF exposure on consumption and BMI.
Results: A total of 3620 participants had data for height and weight from the age 13 clinic and the frequency of FF outlet visits, and so were included in these analyses. This SEM model of food choices showed that increased frequency of eating at FF outlets is positively associated with higher consumption of unhealthy foods (b ¼ 0.29, Po0.001) and negatively associated with the consumption of healthy foods (b ¼ À1.02, Po0.001). The SEM model of FF exposure and BMI showed that higher exposure to FF increases the frequency of visits to FF outlets (b ¼ 0.61, Po0.001), which is associated with higher body mass index standard deviation score (BMISDS; b ¼ 0.08, Po0.001). Deprivation was the largest contributing variable to the exposure (b ¼ 9.2, Po0.001).
Conclusions: The teenagers who ate at FF restaurants consumed more unhealthy foods and were more likely to have higher BMISDS than those teenagers who did not eat frequently at FF restaurants. Teenagers who were exposed to more takeaway foods at home ate more frequently at FF restaurants and eating at FF restaurants was also associated with lower intakes of vegetables and raw fruit in this cohort.
International Journal of Obesity (2011) 35, 1325–1330; doi:10.1038/ijo.2011.120; published online 28 June 2011 Keywords: fast food; overweight; ALSPAC
Childhood obesity prevalence have risen dramatically in the
last 30 years in the Western world with the most recent
figures for England and Wales show that 17% of boys and
16% of girls are obese.1 An increase in the availability of
calorie dense foods is implicated as one of the factors in the aetiology of the obesity epidemic. Fast food (FF) is one section of the food market that has grown steadily over the last few decades and it was worth d8.9 billion in the United Kingdom
in 2005.2 FF is typically quick, convenient, cheap and
Correspondence: Dr LK Fraser, School of Geography, University of Leeds, University road, Leeds LS2 9JT, UK.
Received 6 February 2011; revised 21 April 2011; accepted 12 May 2011; published online 28 June 2011
uniform in its production,3 but FF is often high in saturated fats, energy dense and has low micronutrient content.4–9
Studies from the United States of America have shown that
children who consume FF (when compared with children
who do not eat FF) have higher energy intake and higher fat
intakes9,10 as well as lower vegetable and milk intake.10,11 Therefore, the consumption of such foods could possibly
result in a positive energy balance; and hence, weight gain. There is some evidence from longitudinal studies in the
United States of America that consuming FF as a teenager can result in weight gain in both early12 and middle adulthood.13 FF is often marketed to children and adolescents through
television, internet and movie advertising,14–17 with brand...