My asthma completely disappeared when I followed a No Starch Diet (which I did for about 10 years) to treat my autoimmune disease Ankylosing Spondylitis (AS). A bunch of other immune problems also eased eg iritis, dermatitis, and also peripheral joint inflammation not directly associated with AS.
The No Starch Diet is comparable to Paleo, but a bit stricter:
- Yes: most fruit .. except no to banana and stone fruits
After eating Natto (Japanese cultured soy beans) I was able to resume eating starchy foods without the asthma recurring (except curiously have to avoid peanuts, and not too much cheese). Only in extreme conditions did the asthma return eg a cold causing me to cough a lot and then maybe some asthma until the cold abated.