Non-smokers are still at risk of developing chronic obstructive pulmonary disease (COPD) in their 30s, experts warn.
While emphysema is most commonly caused by smoking, younger people can also develop the lung disease as a result of genetic conditions.
The progressive lung condition is commonly found in people aged 40 and older, however, in recent times more and more patients under 30 are being diagnosed.
Dr Keith Prowse, chairman of the British Lung Foundation, explained: "There’s a condition called alpha-1 antitrypsin deficiency… where the lungs’ defence against emphysema is almost obliterated in one area genetically.
"What that means is that the majority of people who have that … will get emphysema earlier in life than they would normally – say 30s or 40s if they don’t smoke, but into their teens, 20s and 30s if they do."
According to the National Centre for Health Statistics, over four million people in the US were diagnosed with emphysema in 2006.
