The association between ownership of common household devices and obesity and diabetes in high,middle and low income countries

Background:

Household devices (e.g., television, car, computer) are common in high income countries, and their use has been linked to obesity and type 2 diabetes mellitus. We hypothesized that device ownership is associated with obesity and diabetes and that these effects are explained through reduced physical activity, increased sitting time and increased energy intake.

Methods:

We performed a cross-sectional analysis using data from the Prospective Urban Rural Epidemiology study involving 153 996 adults from high, upper-middle, lower-middle and low income countries. We used multilevel regression models to account for clustering at the community and country levels.

Results:

Ownership of a household device increased from low to high income countries (4% to 83% for all 3 devices) and was associated with decreased physical activity and increased sitting, dietary energy intake, body mass index and waist circumference. There was an increased odds of obesity and diabetes with the ownership of any 1 household device compared to no device ownership (obesity: odds ratio [OR] 1.43, 95% confidence interval [CI] 1.32–1.55; diabetes: OR 1.38, 95% CI 1.28–1.50). Ownership of a second device increased the odds further but ownership of a third device did not. Subsequent adjustment for lifestyle factors modestly attenuated these associations. Of the 3 devices, ownership of a television had the strongest association with obesity (OR 1.39, 95% CI 1.29–1.49) and diabetes (OR 1.33, 95% CI 1.23–1.44). When stratified by country income level, the odds of obesity and diabetes when owning all 3 devices was greatest in low income countries (obesity: OR 3.15, 95% CI 2.33–4.25; diabetes: OR 1.97, 95% CI 1.53–2.53) and decreased through country income levels such that we did not detect an association in high income countries.

Interpretation:

The ownership of household devices increased the likelihood of obesity and diabetes, and this was mediated in part by effects on physical activity, sitting time and dietary energy intake. With increasing ownership of household devices in developing countries, societal interventions are needed to mitigate their effects on poor health.The increasing global prevalence of obesity and type 2 diabetes mellitus has been driven predominantly by increases in high income countries.^1,2 However, increases are expected in low and middle income countries, due in part to rapid development and industrialization.Proximal determinants of obesity and diabetes include energy expenditure and intake;^3–5 however, the upstream factors are complex and entail numerous environmental factors. Of these, the increased use of common household devices (e.g., televisions, cars, computers) has been linked to increased sitting, decreased physical activity, obesity, metabolic syndrome and diabetes.^6–12 Time spent watching television has also been linked to poor diet¹³ and increased caloric intake.¹⁴ However, these findings are based on studies in high income countries where the ownership of these devices is common.^15,16 In low and middle income countries, such household devices are less prevalent, but their prevalence is rapidly increasing. Studies in countries with greater variability in the ownership of household devices are needed to understand the full effect of owning such devices on the risk of obesity and diabetes.We hypothesized that the ownership of a television, car or computer would be associated with an increased risk of obesity and diabetes and that these effects would be explained by reduced physical activity, increased sitting time and increased energy intake.     

Preference of Tilapia rendalli (Boulenger) for some species of aquatic plants

Preference of juvenile red-breasted bream, Tilapia rendalli (Boulenger), for the macrophytes Ceratophyllum demersum L., Lagarosiphon ilicifolius (Oberm), Najas pectinata (Magnus) and Valisneria aethiopica (Frenzl) was determined. Fish were offered a mixture of the four macrophytes in equal quantities to determine selection. Preference was shown for V. aethiopica , whilst C. demersum was least selected. This preference order was checked by examination of stomach contents of fish from the same population in the wild and the differences are discussed.