摘要：Objectives. We used self-reported and measured height and weight data to examine the relationship between food insecurity and obesity. Methods. We defined food insecurity according to 3 different models. We used self-reported and measured height and weight from 2 versions of the Canadian Community Health Survey to calculate obesity rates. Results. When self-reported height and weight data were used in calculating obesity prevalence rates, rates were significantly higher among food-insecure respondents than among food-secure respondents; by contrast, when measured height and weight data were used, there were no significant differences. Female respondents classified as food insecure and experiencing mild hunger were at greater risk of obesity than were food-secure female respondents when measured height and weight were used. Conclusions. Associations between obesity and food insecurity are more pronounced when self-reported data on height and weight are used than when measured height and weight data are used. Caution should be used when using self-reported data to examine the relationship between food insecurity and obesity. Food security is recognized as an important determinant of health, 1 , 2 and both food insecurity and obesity are emerging public health concerns. The relationships among inadequate nutrient intake, poor health, and food insecurity are well established in the literature. 3 – 19 However, an evolving body of research investigating the association between body mass index (BMI; weight in kilograms divided by height in meters squared)—obesity in particular—and food insecurity has revealed contradictory findings in Canada, the United States, and other countries. 2 , 8 , 12 , 20 – 22 For example, an analysis of 1998–1999 Canadian National Population Health Survey data revealed that residents of food-insecure households were 1.5 times more likely than residents of food-secure households to be obese (i.e., BMI ≥ 30 kg/m2) when age, gender, and income were taken into account. 3 By contrast, in a later examination of food insufficiency, Vozoris and Tarasuk, 17 using data from the 1996–1997 version of the same Canadian survey, found no significant association between household food insufficiency and BMI among female respondents and significantly decreased odds of overweight (i.e., BMI of 25.0–29.9) among male respondents after they controlled for age, education, and income adequacy. Similarly conflicting findings have been uncovered in US studies. For instance, research involving a representative sample of US households revealed that, among female respondents, food insecurity was positively associated with being overweight. 16 This finding was supported by another US study showing that women in food-insufficient households were more likely than women in food-sufficient households to be overweight and to consume poor diets. 21 Conversely, in a study of adults residing in 2 US states, Laraia et al. concluded that there was no association between overweight and obesity with concerns about food sufficiency after they controlled for education, income, race/ethnicity, marital status, and general health. 22 Further contradictory findings from an analysis of the Third National Health and Nutrition Examination Survey demonstrated that younger girls (aged 2 to 7 years) from all racial/ethnic groups who lived in food-insufficient households were at lower risk of being overweight than were younger girls who lived in food-sufficient households, whereas the opposite pattern was found among older (aged 8 to 16 years) non-Hispanic White girls. 15 It is clear from the discrepancies just described that differences between studies in measurements of food insecurity and food insufficiency, definitions of overweight and obesity, and choices of confounding variables result in both confusion and complexity in terms of delineating the relationship between food insecurity and BMI. The majority of previous research has relied on self-reported measures of height and weight to examine BMI and food insecurity. 3 , 14 , 15 , 20 , 22 To our knowledge, no research in Canada to date has employed national data on measured height and weight to examine the relationship between food insecurity and obesity. Recent trends show that rates of obesity are higher when measured data on height and weight are used in calculating obesity than when self-reported height and weight are used. 23 In addition, associations derived from most previous research involving self-reports (the Townsend et al. 16 study is an exception) do not account for underreporting of weight or overreporting of height. Given the potential consequences of both food insecurity and obesity on individual health and related health care system costs, it is important to understand how obesity relates to food insecurity. Therefore, we sought to provide a unique look at the association between obesity and food security by assessing data on measured height and weight as well as comparative data on self-reported height and weight.
