There isn't a single "normal lung age," but rather a developmental trajectory and a subsequent decline. Lung development is largely complete by 20-25 years old. After around age 35, a gradual decline in lung function is considered normal.
Lung Development and Decline
- Maturity: Lungs reach maturity between 20 and 25 years of age. This means they have reached their full potential in terms of growth and capacity. (Source: Multiple sources including American Lung Association and other studies)
- Gradual Decline: Starting around age 35, a decrease in lung function is a natural part of aging. This decline is gradual and varies from person to person. (Source: American Lung Association, various research articles)
- Factors Affecting Lung Function: Several factors influence lung function, including age, sex, height, body mass index (BMI), ethnicity, and overall health. (Source: Research articles on lung function reference values). These factors are considered when assessing lung health and determining if a decline is outside the normal range.
- Testing: Spirometry and other breathing tests are used to assess lung function. Normal ranges are calculated based on these individual factors. (Source: Research articles detailing spirometry reference ranges and studies on lung function testing).
It is important to note that while a decline in lung function after 35 is typical, the rate and severity of this decline vary considerably. Maintaining a healthy lifestyle through regular exercise, avoiding smoking, and managing underlying health conditions can help to slow the rate of this decline and support optimal lung health throughout life.
