(CBS) Soda drinkers can't seem to catch a break these days. A new study suggests drinking soda might raise the risk for respiratory diseases like asthma and chronic obstructive pulmonary disease (COPD).
For the study, published in the Feb. 7 issue of Respirology, Australian researchers surveyed nearly 17,000 people asking about their soft drink habits. For this study's purposes, soft drinks included Coke, lemonade, flavored mineral water, Powerade, and Gatorade, and all other types of soda, the researchers said.
What did they find?
One in 10 Australian adults drink more than half a liter of soft drink per day - that's more than two cups. But that amount was tied to "dose-response relationship" with risk for asthma and COPD, meaning the more soft drinks people consume, the higher their risk. Overall, 13.3 percent of surveyed participants with asthma and 15.6 percent of those with COPD drank more than two cups of soda each day.
What does drinking soda have to do with lung health? The study authors said one reason may be drinking soda is tied to an increased risk for obesity, which raises risk for asthma and COPD.
"Our study emphasizes the importance of healthy eating and drinking in the prevention of chronic diseases like asthma and COPD," study author Dr. Zumin Shi, a research fellow at the University of Adelaide in Australia, said in a written statement.
The study did not prove cause-and-effect, only an observational link, so some experts thought many unhealthy factors contributed to the raised risk.
"High soda intake is a good marker for poor overall diet, and poor overall attention to health," Dr. David Katz, director of the Prevention Research Center at Yale University in New Haven, Conn., told MedPage Today. "It likely suggests greater exposure to everything from tobacco smoke to air pollution."
This study is far from the first to tie drinking soda to health risks.
A 2010 study in the journal, "Diabetes Care," found daily soda drinkers were 25 percent more likely to develop type 2 diabetes,
What should people be drinking? The CDC has more information on healthy beverages, on its "Rethink Your Drink" site.