About two years ago, I was diagnosed with asthma. After some changes to my lifestyle, the last whole body plethysmography measurement showed that my lungs are fine again although I do not use any medication anymore. The asthma is gone!
I would like to share these changes with you, hoping they may also benefit you and also to hear back what benefited others and what not. My personal experiment is a little small (n=1), thus it may well be that some improvement were just by accident and not because of lifestyle change. I have to say that I only had very light asthma. I never had an asthmatic attack, but regularly did wheeze lightly when exhaling at night, my voice was not so strong anymore and my lungs produced too much mucus (leading to some coughing and a coated tongue). Another sign was that the reliever medication (Bronchodilators) made jogging a lot easier.
Asthma is on the rise the last 50 years in the West. Already this points to lifestyle factors being important. Not much seems to be known about which factors these are. It has been noted that children growing up at farms as less affected by asthma as urban children. Based on this, it has been theorized that childhood contact with microbes is beneficial, but I guess there are quite a few other differences between the life on the country side and in cities.
The main changes I made are that I started with intermittent fasting, and nowadays sleep on a firm surface, and do much more walking/hiking. Also important may have been that I do not any grains any more, do less jogging and more sprinting and that I regularly tanning for more vitamin D.