Overweight and obesity in the young and old: Prevalence, prevention and eating behavior

Abstract

ABSTRACT Background: During the last 25 years the prevalence of overweight and obe-sity has increased dramatically, both in developed and developing countries. The World Health Organization is declaring it an epidemic. In Sweden the increase was almost 50% between 1980 and 2005. The largest increases oc-curred in the 16-24-year age group. The highest prevalence can be observed in older age groups.

The general aim of this thesis is to study obesity and its determinants in the young and the elderly. The specific aims are to document secular trends in overweight and obesity and lifestyle determinants in the elderly, to investi-gate the influence of genetic and environmental factors in body shape and behavioral aspects of weight in teenagers and to conduct an intervention study to prevent overweight and obesity in young high-risk women.

Methods: Five cross-sectional samples of 3 702 70-year-olds born between 1901 and 1930 in Göteborg, Sweden were examined in the Gerontological and Geriatric Population Studies (H70). Cohort differences in anthropomet-ric parameters and lifestyle determinants such as diet, physical activity, smoking habits and education were assessed.

The Twin Study of Child and Adolescent Development (TCHAD) is a population-based longitudinal study including all twin pairs born in Sweden between 1985 and 1986. The 15-17-year-old twins reported their anthro-pometric data and answered a questionnaire about body image and disor-dered eating. Respective genetic and environmental influences were esti-mated.

Young women, aged 18-28, with severely obese parents, were randomized to control or intervention groups in which they participated in a year-long in-dividualized behavioral program (Health Hunters) focusing on diet and physical activity.

Results: The prevalence of overweight and obesity increased in 70-years-olds and was about 65% and 22% respectively in 2000. BMI increased in all life-style groups, but the increase was lowest among the physically active. Many secular changes in food selection patterns were observed in the elderly and the nutritional content of their diets was generally adequate.

In the young twins, genetic factors had a major effect on anthropometric parameters while environmental factors were most important for body image and eating behavior.

Young women with a familial predisposition to obesity were at high risk for weight gain; however the Health Hunters prevention program succeeded in preventing weight gain.

Conclusion: Both the young and the elderly are afflicted by the obesity epi-demic. Research activities and prevention initiatives must draw attention to both age groups. Our results indicate the importance of focusing on body image in the young, while diet and physical activity are relevant for all age groups. Working with prioritized groups is one component of managing the obesity epidemic.