Study Reveals Early Decline in Lung Capacity Starting at Age 20

A recent study conducted by the Barcelona Institute for Global Health (ISGlobal) in collaboration with Clínic-IDIBAPS has uncovered significant insights into the evolution of lung capacity throughout a person's life. This research, published in The Lancet Respiratory Medicine, offers a new framework for evaluating lung health from childhood to old age.

Historically, it was believed that lung function would peak around the ages of 20 to 25 and then stabilize, with a decline commencing only in later adulthood. However, this perception was based on research that did not account for the entire lifespan. The current study utilized an innovative "accelerated cohort design," merging data from multiple cohort studies to encompass a broader age range.

More than 30,000 participants aged 4 to 82 years from various population-based studies across Europe and Australia were included in this comprehensive analysis. Judith Garcia-Aymerich, the study's first author and co-director of ISGlobal's Environment and Health program, noted the extensive scope of the research.

The assessment of lung capacity involved forced spirometry, a test to measure how quickly a person can exhale after a deep inhalation. Data regarding factors like active smoking and asthma diagnosis were also integrated into the study.

The study identified two distinct phases of lung function development: a rapid growth phase during childhood and a slower growth phase leading to peak lung function. It was observed that the forced expiratory volume in one second (FEV1) reaches its peak around age 20 for women and age 23 for men. Notably, the research indicated that a stable phase does not follow this peak; instead, lung function begins to decline immediately thereafter, contrary to previous models that suggested a plateau until age 40.

Moreover, the findings revealed that chronic asthma and smoking impact lung function in unexpected ways. Individuals with persistent asthma tend to reach an earlier peak in FEV1 and maintain lower levels of lung function throughout their lives. Smoking, however, is associated with a more rapid decline in lung capacity beginning around age 35.

These revelations underline the urgency of promoting respiratory health and implementing early monitoring of lung function with spirometry. Rosa Faner, a researcher at the University of Barcelona and a co-author of the study, emphasized that early identification of reduced lung function could facilitate interventions aimed at preventing chronic respiratory diseases in adulthood.

For further details, refer to the original research: Garcia-Aymerich, J., et al. General Population-Based Lung Function Trajectories Over The Life Course. An Accelerated Cohort Study. The Lancet Respiratory Medicine (2025).