Relationship of soft drink consumption to global overweight, obesity, and diabetes: a cross-national analysis of 75 countries

Abstract

Objectives: We estimated the relationship between soft drink consumption and obesity and diabetes worldwide.

Methods: We used multivariate linear regression to estimate the association between soft drink consumption and overweight, obesity, and diabetes prevalence in 75 countries, controlling for other foods (cereals, meats, fruits and vegetables, oils, and total calories), income, urbanization, and aging. Data were obtained from the Euromonitor Global Market Information Database, the World Health Organization, and the International Diabetes Federation. Bottled water consumption, which increased with per-capita income in parallel to soft drink consumption, served as a natural control group.

Results: Soft drink consumption increased globally from 9.5 gallons per person per year in 1997 to 11.4 gallons in 2010. A 1% rise in soft drink consumption was associated with an additional 4.8 overweight adults per 100 (adjusted B; 95% confidence interval [CI] = 3.1, 6.5), 2.3 obese adults per 100 (95% CI = 1.1, 3.5), and 0.3 adults with diabetes per 100 (95% CI = 0.1, 0.8). These findings remained robust in low- and middle-income countries.

Conclusions: Soft drink consumption is significantly linked to overweight, obesity, and diabetes worldwide, including in low- and middle-income countries.

FIGURE 1—

Relationship of soft drink consumption to the prevalence of (a) overweight among adults older than 20 years, (b) obesity among adults older than 20 years, and (c) diabetes among adults aged 20–79 years. Note. The curves on the graphs are the product of a robust locally weighted nonparametric regression describing the smoothed relationship between the x- and y-axis variables. The locally weighted regression is performed with the Stata lowess algorithm in which bandwidth*N observations are used to calculate a smoothed value for each point in the curve; the default bandwidth is 0.8 and n = 79 countries. Consumption is the annual average from 1997 to 2007 to reflect both the lagged and cumulative impact of consumption on body mass and diabetes. Y-axis variables are unadjusted in these figures. Bandwidth  = 0.8.

FIGURE 2—

Soft drink consumption in US gallons per capita per year worldwide (a) over time and (b) vs GDP for the year 2010. Note. GDP = gross domestic product; PPP = purchasing power parity. GDP per capita is expressed in 2005 international dollars PPP for comparability between countries. Bandwidth  = 0.8.