He's admitted he knows how 'frightening' it can be when struggling to breathe, as part of a charity campaign.
Stephen Fry's encouraging people to look after their lung health - warning "we mustn't take our breathing for granted".
The actor, who has asthma, has written a letter which says 12-million people will be diagnosed with a condition related to the organ in their lifetime.
He's admitted he knows how 'frightening' it can be when struggling to breathe, as part of a charity campaign.