How to Respond to the Soft Drink–Asthma and COPD Connection

February 22, 2012

The evidence from a large risk surveillance is robust. The study even controlled for intake of fruits, vegetables, water, and juice. Here are suggestions for patients who may find it difficult to break the habit.

The report that carbonated beverages may contribute to the risk of asthma and chronic obstructive pulmonary disease (COPD) not surprisingly received wide news coverage. You may even have heard about it from some patients. Just consider it more good reason to urge parents to wean their children off soft drinks and adult patients to trade soda for something more nutritious.

Published in the journal Respirology, the study found a 26% increased risk of asthma, a nearly 80% increased risk of COPD, and a more than 2-fold increased risk of both diseases among persons who consume just 2 cans of soda a day compared with those who don’t drink any.1

Researchers from the University of Adelaide in Australia analyzed data from a risk surveillance system of 16,907 individuals aged 16 and older conducted between March 2008 and June 2010, which had a 12.5% prevalence of asthma and 4.4% prevalence of COPD. While 11.4% of those surveyed reported consuming 16 ounces or more of soft drinks a day, 13.3% of those with asthma and 15.6% of those with COPD reported drinking that amount on a daily basis.

The researchers controlled for age, sex, education, income, area of residence, smoking, alcohol consumption, physical activity, being overweight, intake of fruits and vegetables, and intake of water and juice, which makes their findings even more robust.

So what’s going on? The authors aren’t sure, but they offer a few theories. One is that the inflammation triggered by large amounts of sugar could increase the risk of both conditions, something seen in at least one animal study.2 Other possibilities include the effect of chemicals such as phthalates found in plastic soda bottles, which have been linked to an increased risk of asthma.3 Also, some people might be allergic to the preservatives in the soft drinks.

To help your patients to switch from soda to healthier options, you might suggest that they:

• Switch gradually. Cut back on 1 soda each day until they are drinking 1 or fewer soft drinks.
• Switch to something healthier. Water is best, but if they don’t like the taste of water, suggest adding lemon, lime, or even fresh mint leaves. Unsweetened, flavored soda water is a good option for people who enjoy the carbonation.


1. Shi Z, Grande ED, Taylor AW, et al. Association between soft drink consumption and asthma and chronic obstructive pulmonary disease among adults in Australia. Respirology. 2012;17:363-369.
2. Kierstein S, Krytska K, Kierstein G, et al. Sugar consumption increases susceptibility to allergic airway inflammation and activates the innate immune system in the lung. J Allergy Clin Immunol. 2008;121:S196.
3. Bornehag CG, Nanberg E. Phthalate exposure and asthma in children. Int J Androl. 2010;33:333–345.