Adult Obesity

Objectives: Based on direct measures of height and weight, this article compares the prevalence of obesity among adults aged 18 or older in 1978/79 and 2004. Prevalence by demographic, socio-economic and lifestyle characteristics is presented, along with associations between obesity and selected chronic conditions. Canadian and US data are also compared.

Data Sources: Data are from the 2004 Canadian Community Health Survey: Nutrition, the 1978/79 Canada Health Survey and the 1986 to 1992 Canadian Heart Health Surveys. US data are from the 1999-2002 National Health and Nutrition Examination Survey.

Analytical Techniques: Descriptive statistics were used to estimate the proportion of adults who were obese in 2004 in relation to selected characteristics. Logistic regression models were used to examine relationships between obesity and high blood pressure, diabetes and heart disease, controlling for socio-economic status and other risk factors such as smoking and physical activity.

Main Results: In 2004, 23% of adults, 5.5 million people aged 18 or older, were obese--up substantially from 14% in 1978/79. An additional 36% (8.6 million) were overweight. Obese individuals tended to have sedentary leisure-time pursuits and to consume fruit and vegetables infrequently. As body mass index (BMI) increased, so did an individual's likelihood of reporting high blood pressure, diabetes and heart disease.