Association between soft drink consumption and asthma and chronic obstructive pulmonary disease among adults in Australia

Background and objective: The aim of this study was to examine the association between soft drink consumption and self-reported doctor-diagnosed asthma and COPD among adults living in South Australia. Methods: Data were collected using a risk factor surveillance system. Each month a representative random sample of South Australians were selected from the electronic White Pages and interviews were conducted using computer-assisted telephone interviewing (CATI). Results: Among 16 907 participants aged 16 years and older, 11.4% reported daily soft drink consumption of more than half a litre. High levels of soft drink consumption were positively associated with asthma and COPD. Overall, 13.3% of participants with asthma and 15.6% of those with COPD reported consuming more than half a litre of soft drink per day. By multivariate analysis, after adjusting for socio-demographic and lifestyle factors, the odds ratio (OR) for asthma was 1.26 (95% confidence interval (CI): 1.01-1.58) and the OR for COPD was 1.79 (95% CI: 1.32-2.43), comparing those who consumed more than half a litre of soft drink per day with those who did not consume soft drinks. Conclusions: There was a positive association between consumption of soft drinks and asthma/COPD among adults living in South Australia. Soft drink consumption has been linked to a range of chronic diseases but no previous study was focused on the association with asthma/COPD. Among 16 907 participants aged 16 years and older living in South Australia, a positive association was identified between consumption of soft drinks and the risk of asthma/COPD.