How Your Lungs Change as You Age

Your lungs are amazing, hard-working organs, but they are not immune to the passage of time. As you age, so do your lungs, and it's helpful to understand how your lungs change so you know when something is amiss. We spoke with Francesca Polverino, MD, PhD, physician scientist and tenured professor of medicine at the Baylor College of Medicine, about these changes and what we can do to slow them down.

Lungs 101: How They Work

How Do Your Lungs Change?

The maximum amount of air your lungs can hold—your total lung capacity—is about six liters. That is about three large soda bottles. “During your 20s, your lungs typically function at their peak, but aging naturally reduces elasticity in lung tissues, narrows airways, and weakens the muscles involved in breathing,” says Dr. Polverino. “Lung function begins to decline gradually between 30 and 35, although many people are unaware this process starts so early.”

Specifically, your lungs begin to lose elasticity, making it harder for them to expand and contract. The alveoli begin to enlarge, which decreases their surface area and impairs oxygen transfer. The diaphragm and other breathing muscles lose strength, decreasing the ease of inhaling and exhaling. Rib bones become thinner and change shape, altering the ribcage so that it is less able to expand and contract with breathing. Your airway walls may become thicker and narrower, increasing airflow resistance. And your immune system's overall response in the lungs also weakens, leaving you more vulnerable to infections like pneumonia and bronchitis.

For most people, this gradual decline becomes more noticeable in their 60s or 70s. Around this time, it is normal to experience some symptoms like mild breathlessness during strenuous activities or a mild cough in the morning. More severe symptoms that may indicate lung disease include persistent shortness of breath during everyday activities, a chronic cough that lingers for weeks or months, wheezing, chest tightness, and frequent respiratory infections. “Distinguishing between normal aging and disease is important,” she continues.

“For instance, a 68-year-old who becomes winded after climbing stairs but can walk a mile without issue and has normal spirometry likely does not have significant pathology. Conversely, a young adult with mild symptoms but a history of preterm birth or childhood asthma might require further evaluation.”

What Can Accelerate Lung Decline?

It’s important to understand that the rate of decline is not fixed. In fact, it's strongly influenced by lifestyle, environmental exposure and overall health. The number one factor that can speed up lung decline and cause earlier onset of respiratory symptoms and disease is cigarette smoking. “One pack per day can potentially double or triple the rate of decline compared to non-smokers. This can lead to chronic bronchitis, emphysema or irreversible airflow obstruction,” says Dr. Polverino.

Environmental factors like exposure to long-term air pollution can also contribute to lung decline. For instance, people who work in fields like construction, agriculture or manufacturing —where they regularly inhale dust, chemicals or fumes without proper protection —often show signs of accelerated lung aging. Respiratory infections caught early in life, especially those left untreated, can result in long-term scarring. “We know that lung health is shaped well before adulthood, so pre- and perinatal factors can also influence both lung growth and the trajectory of lung aging,” Dr. Polverino continues.

Additionally, a sedentary lifestyle can indirectly cause lungs to prematurely age by weakening respiratory muscles and reducing ventilation. Obesity can further restrict lung expansion, leading to shallow breathing and poor oxygen exchange.

What Can Slow Lung Decline? 

Currently, there is no evidence that suggests that the lungs can regenerate, which is why prevention is the best way to slow aging and keep your lungs healthy. “To slow decline, I encourage patients to stay physically active with regular aerobic exercise such as walking, swimming or biking. These activities help maintain lung capacity and respiratory muscle strength,” says Dr. Polverino.

She also stresses trying to protect your lungs from occupational hazards like dust or fumes by using respirators and improving ventilation. At home, find ways to improve your indoor air quality. This could include eliminating dust and mold, using air cleaners and avoiding harsh chemicals.

Vaccines are another essential tool that can help protect aging lungs. As the immune system weakens with age, older adults become more likely to catch severe respiratory infections and experience severe symptoms that can quickly worsen lung function. Vaccines help prevent these infections and reduce their severity, which in turn protects lung tissue from further damage. Currently, annual flu, RSV, COVID-19 and pneumococcal vaccines are recommended for all adults over the age of 60.

Most importantly, it is crucial to avoid smoking or quit smoking if you are currently using tobacco products. Tobacco use significantly accelerates lung damage, but even individuals who quit later in life can reap the benefits. “One of my patients who was in her 50s with early-stage COPD found that after quitting smoking, starting daily walks and managing her medications properly, her lung function stabilized and has remained steady for over three years,” shared Dr. Polverino. “It just shows that decline is not always inevitable.”

Her final plea is not to take your lung health for granted. "Because the lungs have a high functional reserve, symptoms may only appear after significant loss. That’s why maintaining and protecting this reserve through healthy habits and routine check-ups is so important, even when you feel fine,” she says. “You can’t undo lung aging once it reaches an advanced stage, but prevention and early intervention are possible.”

Learn more about how your lungs work and how to keep them healthy.