Overweight and obesity: The air “thickens”

Fat deposits in the lungs trigger chronic inflammation and narrowing of the airways. Is this ultimately an explanation for the higher asthma burden and other breathing problems in overweight people?

Lung fat constricts the respiratory tract

According to a new study, obesity also "fattens" the respiratory tract. Fat deposits in the lungs trigger chronic inflammation and narrowing of the airways. Is this ultimately an explanation for the higher asthma burden and other breathing problems in overweight people? 

Overweight and obesity can already be described as a worldwide epidemic. Lack of exercise and unhealthy nutrition are their main causes. Many overweight people suffer shortness of breath and asthma much more frequently than people of normal weight.

One possible explanation for this is proposed by a recent study from Australia, which found more fat deposits in the respiratory tract in the lung tissue of overweight patients. There is obviously a direct connection with the body mass index (BMI) because the higher the BMI was among the participants, the more fat they stored in their airways’ walls.

Such fat deposits in the lungs probably lead to a mechanical narrowing of the respiratory tract, and fat tissue promotes inflammatory reactions which make breathing even more difficult. As a result, some overweight people suffer from shortness of breath and more frequent asthmatic symptoms.

Whether weight loss can reverse these changes has not yet been investigated. In the meantime, treating physicians should nevertheless recommend their patients to reduce their weight, if only to counteract breathing problems caused by the increased pressure from their own body weight.

Sources:
Press release of the European Lung Foundation from 18.10.2019; https://www.europeanlung.org/en/news-and-events/media-centre/press-releases/study-provides-first-evidence-that-fat-accumulates-in-the-lungs-of-overweight-and-obese-people
Elliot JG et al., Fatty Airways: Implications for Obstructive Disease. European Respiratory Journal 2019; doi:10.1183/13993003.00857-2019 [Original Publication]