Public Health Nutrition

Research Paper

The prevalence of underweight in 9–10-year-old schoolchildren in Liverpool: 1998–2006

Lynne M Boddya1a2 c1, Allan F Hacketta1a2 and Gareth Strattona1

a1 Research into Activity and Children’s Health Group, Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Henry Cotton Campus, Liverpool, UK

a2 Centre for Tourism, Consumer and Food Studies, Liverpool John Moores University, IM Marsh Campus, Barkhill Road, Liverpool L17 6BD, UK


Objective To estimate the prevalence of underweight between 1998 and 2006 in Liverpool schoolchildren aged 9–10 years using recently published underweight cut-off points.

Design and setting Stature and body mass data collected at the Liverpool SportsLinx project’s fitness testing sessions were used to calculate BMI.

Subjects Data were available on 26 782 (n 13 637 boys, 13 145 girls) participants.

Results Overall underweight declined in boys from 10·3 % in 1998–1999 to 6·9 % in 2005–2006, and all sub-classifications of underweight declined, in particular grade 3 underweight, with the most recent prevalence being 0·1 %. In girls, the prevalence of underweight declined from 10·8 % in 1998–1999 to 7·5 % in 2005–2006. The prevalence of all grades of underweight was higher in girls than in boys. Underweight showed a fluctuating pattern across all grades over time for boys and girls, and overall prevalence in 2005–2006 represents over 200 children across the city.

Conclusions Underweight may have reduced slightly from baseline, but remains a substantial problem in Liverpool, with the prevalence of overall underweight being relatively similar to the prevalence of obesity. The present study highlights the requirement for policy makers and funders to consider both ends of the body mass spectrum when fixing priorities in child health.

(Received October 09 2007)

(Accepted April 03 2008)


c1 Corresponding author: Email