What is the association between soft drink consumption and prevalence of overweight and obesity in adolescents?

By Hugo Francisco de SouzaJul 31 2023Reviewed by Benedette Cuffari, M.Sc.

In a recent study published in JAMA Network Open, researchers review data from studies encompassing adolescents from 107 countries and regions to elucidate the association between soft drink consumption and excessive weight gain. The study findings suggest that daily soft drink consumption is strongly associated with overweight and obesity.

Study: Consumption of Soft Drinks and Overweight and Obesity Among Adolescents in 107 Countries and Regions. Image Credit: AN Photographer2463 / Shutterstock.com

Soft drinks and weight gain

Soft drink consumption has been scientifically verified to cause weight gain in humans. One of the hypotheses for the increased incidences of overweight and obese people globally is related to increased carbonated drink consumption, irrespective of a nation’s income bracket.

Research on adults has found an association of 1% increased soft drink intake corresponding to a 4.8% greater risk of future overweight or obesity. To date, there remains a lack of similar studies among school-age adolescents, who are often the main target of sugar-sweetened beverages.

About the study

In the present study, researchers review and analyze data aggregated from school-based surveys to evaluate the association between the prevalence of daily soft drink consumption and obesity.

The Global School-Based Student Health Survey (GSHS) comprises data obtained from 13- to 17-year-olds between 2009-2012, whereas the European Health Behavior in School-Aged Children (HBSC) cohort includes North American and European adolescents’ data between 2017 and 2018. The final records database included in the study was from the 2019 U.S. National Youth Risk Behavior Survey (YRBS).

A post-hoc classifier was assigned to each individual to categorize them according to their daily soft drink consumption habits. Daily consumption comprised students who consumed one or more carbonated beverages daily, whereas nondaily consumption included those who never or occasionally consumed soft drinks.

This data was combined with direct body mass index (BMI) measurements from GSHS and corresponding self-reports from HBSC and YRBS to analyze the prevalence of individuals who were ‘overweight’ and ‘obese.’ Covariates like daily fruit and vegetable consumption, age, sex, physical activity, and socioeconomic variables, including national soft drink tax and country income groups, were also considered for the analysis.

For country-level analyses, researchers built two models, one that adjusted for the age and number of women in each country and the other which adjusted for all variables excluding age and sex. Individual-level analyses used logistic regression models to evaluate the correlation between overweight/obesity and soft drink consumption.

Study findings

About 17.2% of the 405,528 students included in this study were either overweight or obese. The mean age of the students was 14.2 years, with 51.6% of the cohort female. Almost 33% of all students were classified as daily soft-drink consumers.

The soft-drink tax was found to be an effective deterrent against carbonated beverage consumption, with a lower prevalence of both daily consumers and overweight students from countries imposing the tax.

Cambodia had the lowest number of overweight students at 3.3% as compared to 64% in Niue. Niue also had the highest daily beverage consumption rate of 79.6% as compared to Iceland, which had the lowest soft drink consumption rate of 3.3%.

The country-level incidence of overweight and obese individuals increased by 3.7% for every 10% increase in daily soft drink use. At the individual level, daily soft drink consumers were 14% more likely to be overweight than students who consumed less than 250 mL of soft drinks daily.

Study limitations

Some notable limitations of this study include its cross-sectional nature, as it prevents researchers from effectively determining causal associations between soft drink consumption and weight gain.

Additionally, the data collected in the studies were self-reported and, as a result, prone to bias in food and drink consumption. This is especially true for overweight and obese individuals who have been shown to under-report their intake, which may have caused to these analyses to underestimate the strength of the soft drink-weight association.

Additionally, data were collected from school-attending adolescents. The lack of data from adolescents who did not go to school may further affect the generalizability of our findings.”

Conclusions

In the present study, researchers conducted the first evaluation of the association between soft drink consumption and excessive weight gain. To this end, a positive association between daily soft drink consumption and overweight and obesity prevalence was observed. The study also revealed that the taxation of soft drinks is an effective deterrent in reducing soft drink consumption and potentially excessive weight gain among school-going adolescents.