Longitudinal study of changes in body mass index, anthropometric measures, dietary intake and physical activity in cohorts of school-going Irish adolescents

Project start date: 1 October 2004
Project status: Completed
Project type: Nutrition
Discipline: Nutrition surveillance
Author/s: Dr Nora O’Brien & Dr Tom O‘Connor, University College Cork
Collaborator/s: Single supplier

Research objective

Worldwide, the prevalence of childhood obesity is increasing. Obesity in adolescence is a strong predicator of adult obesity. This project involved a longitudinal study over a 3-year period of changes in Body Mass Index (BMI) and other anthropometric measures together with information on dietary and exercise patterns in a cohort of students in the junior school cycle.

A similar longitudinal survey was conducted in a second cohort of students in the post-junior cycle. This generated new data on the adolescent age group 12-18 yrs. This data is important in understanding the evolution during adolescence of changes in anthropometric measures and dietary and exercise patterns, which tend to be maintained into adulthood where they have a major impact on chronic disease.

Outputs

Research report

Title: Longitudinal study of changes in body mass index, anthropometric measures, dietary intake and physical activity in cohorts of school-going Irish adolescents
Publication date: 1 May 2009
Summary: A 3-year longitudinal study of anthropometric, dietary and exercise parameters was carried out annually (2005 - 2007) in 3 Irish secondary schools.
Findings:
Overweight and obesity were at relatively low levels in these adolescents.
- Height, weight, BMI, waist and hip circumferences and TST increased significantly over the 3 years.
- Waist-to-hip ratio (WHR) decreased significantly over time. Boys were significantly taller than girls across the 3 years.
- A 3-day weighed food diary was used to assess food intake by the adolescents. Analysis of dietary intake data was determined using WISP©.
- Mean daily energy and nutrient intakes were reported. Mean daily energy and macronutrient intakes were analysed longitudinally.
- The adolescents' diet was characterised by relatively high saturated fat intakes and insufficient fruit and vegetable consumption.
- The dietary pattern did not change significantly over the 3 years.
- Boys consumed more energy than girls over the study period.
A validated questionnaire was used to assess physical activity and sedentary activity levels.
- Boys were substantially more active and had higher energy expenditure estimates than girls throughout the study.
- A significant longitudinal decrease in physical activity levels among the adolescents was observed.
- Both genders spent more than the recommended amount of time (hrs/day) pursing sedentary activities.
The dietary pattern in these Irish adolescents is relatively poor. Of additional concern is the overall longitudinal decrease in physical activity levels. Promoting consumption of a balanced diet and increased exercise levels among adolescents will help to reduce future public health care costs due to weight-related diseases.

Other outputs

PhD Thesis

This PhD thesis is available through University College Cork: Longitudinal study of changes in body mass index, anthropometric measures, dietary intake and physical activity in cohorts of school-going Irish adolescents