Hello, just joined today. I didn't develop asthma until 2010 after owning a diesel for two years, but of course the smoking from my teens didn't help either. Managed to kick the habit but use e-cigs now. Haven't had an asthma attack for a few years but had a recent review and my lung capacity is just over 300. Previous reading was 340 about 4 years ago. Should I be worried? The nurse was pretty apathetic and said it should be 550 for someone of my age and build.