Drinking large amounts of sugary soft drinks is associated with the occurrence of chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD), according to research published in the journal Respirology.
“Our research highlights the role of healthy eating and drinking in the prevention of chronic diseases such as asthma and COPD,” comments lead author Dr. Zumin Shi of the University of Adelaide in Australia.
His team analyzed the data collected in telephone interviews among nearly 17 thousand. people aged 16 and over. They concerned the diagnosis of asthma or COPD and the consumption of sweet soft drinks, such as cola, flavored mineral waters, various types of lemonades, and isotonic drinks for athletes.
Statistical analysis – which took into account other lifestyle elements and demographic factors – showed that people consuming more than 0,5 liters of such drinks a day by 26 percent. they more often suffered from asthma and 79 percent. were more likely to have COPD than those who did not drink it at all.
The researchers noted that the relationship was directly proportional to the dose – the more sweetened drinks a person consumed, the more likely they were to have either of the two conditions.
Overall, 11,4 percent. of the respondents admitted consuming more than half a liter of sweet drinks without alcohol each day, while in the group of patients with asthma this percentage was 13,3%, and in the group with COPD – 15,6%.
The analysis included, inter alia, elements of lifestyle, the prevalence of overweight and obesity, and the consumption of vegetables and fruits. Smoking cigarettes further exacerbated the association between drinking sugary drinks without alcohol and the incidence of chronic respiratory disease, especially COPD.
The researchers note that their results do not provide evidence of a causal relationship between the consumption of large amounts of sugary drinks without alcohol and the risk of asthma and COPD.
For now, it is also unclear what mechanism could be responsible for the occurrence of such a dependency. However, researchers put forward several hypotheses.
Both asthma and COPD are associated with inflammation in the lower respiratory tract. It is also known that various components of the diet can contribute to the so-called oxidative stress (associated with excess free radicals) and the development of inflammation. Soft drinks often contain large amounts of simple sugars, and, as previous animal studies have shown, these compounds may increase the predisposition to inflammation in the respiratory system. This is confirmed by the observations that children whose diet contains a lot of simple sugars more often suffer from asthma symptoms.
This sugar is also known to promote overweight and obesity, which have previously been linked to the risk of asthma and COPD. However, when the researchers included obesity in the analysis, the results were the same. In addition, while most soft drinks in Australia are sweetened with sugar, researchers did not have data on the percentage of diet drinks consumed by test subjects.
The authors of the study also recall that there have been reports in the past about the relationship between phthalates that may be released from plastic bottles and the occurrence of asthma. It cannot be ruled out that preservatives present in beverages play a role here – such as nitrogen or sulfur compounds, which may cause allergic reactions.
Nevertheless, taking into account the fact that the consumption of sweet soft drinks has been previously associated with the occurrence of various chronic diseases, the authors of the study estimate that promoting a healthy diet without excess of these drinks may be one of the methods of preventing asthma and COPD.
COPD takes an average of 20-30 years to develop and begins to manifest itself most frequently in elderly and middle-aged people. The main risk factor is smoking. The disease is characterized by chronic inflammation in the respiratory system under the influence of irritants and incompletely reversible obstruction (i.e. narrowing) of the bronchi. Its first symptom is often shortness of breath when climbing stairs, but later on, patients become breathless even during normal activities. In the last phase of the disease, chronic oxygen therapy must be used. COPD – especially if left untreated or if not treated properly – can lead to respiratory disability.
Asthma is a chronic disease of the lower respiratory tract – bronchi and lungs, which develops on an inflammatory basis, mostly in childhood. The chronic inflammatory process in the bronchi is accompanied by their hypersensitivity to various factors, such as allergens, cold air, viruses, and physical exertion. Under their influence, the bronchi constrict, which causes symptoms typical of asthma – shortness of breath, wheezing, cough.
It is estimated that about 4 million people in Poland suffer from asthma symptoms, and about 2-2,5 million suffer from COPD.