Healthy lung function for a person with Winehouse's demographic would probably hover around 80 percent or more, Horovitz said.
"This is not moderate or severe emphysema. It's mild emphysema," Horovitz stressed. "But with the natural aging process, when you're 54, you're going to have moderate to severe emphysema."
The singer's career and young life have been marked by both highs and lows. Her 2006 album, Back to Black won five Grammy awards, including Best New Artist, Record of the Year and Song of the Year. But her alcohol and drug dependencies have been widely reported.
According to MTV News, Mitch Winehouse told the BBC that she is currently "smothered" in nicotine patches to help her kick the smoking habit.
Winehouse understands that "the only thing that can go into her lungs right now is fresh air," her father said. "She doesn't have emphysema, she has traces of it. Obviously, if she doesn't quit smoking, it's going to get worse."
Visit the American Lung Association for more on emphysema.
SOURCES: Len Horovitz, M.D., pulmonary specialist, Lenox Hill Hospital, New York City; Norman Edelman, M.D., chief medical officer, American Lung Association; Associated Press; MTV News