Can Your Lungs Repair Themselves When You Quit Smoking?

You Should Know: Your lungs are more resilient than you might think. For example, they do have a real capacity to heal after you quit smoking. Researchers now understand that the lungs evolved with substantial self-repair mechanisms precisely because they’re constantly exposed to harmful particles and pathogens. When you stop smoking, certain cells that have avoided DNA damage help replenish the airway lining, and tiny hair-like structures called cilia start sweeping out toxins again. Lung function can then improve by as much as 30% within the first few months.

Going Deeper: Some lung damage is still permanent. Emphysema occurs when air sacs rupture and the tissue doesn’t regenerate. After extensive damage, the healing process leads to stiff scar tissue rather than healthy lung tissue. Lungs are also slower to repair themselves as you age.

Takeaway: The lungs can recover a lot, but how much depends heavily on how long and how much someone smoked.

Bottom Line: Quitting smoking always makes a difference — at any age. Still, the idea that your lungs will bounce back completely isn’t entirely true.