Dr. Daniel Dilling, a pulmonologist at the Loyola University Medical Center near Chicago, said lungs are to a certain extent "overbuilt" and have a good deal of reserve volume.
"A person with two lungs has a lot of reserve function, so if one lung is removed, he or she can still function normally, without shortness of breath," Dilling said in a statement. "You can live no problem with one lung."
However, if a person with one lung suffers a lung disease, he or she will not have any reserve capacity to compensate for loss of lung function, Dilling said.
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