My wife has suggested this in the past. She is a physio (a neuro specialist so does not claim to be a respiratory expert) but has some info from training and colleagues. Apparently dairy foods in the diet can cause thicker mucus on the chest and exacerbate breathing problems. A low dairy diet is recommended for children with cystic fibrosis etc.
In the summer months when things are mostly ok I get lazy and forget to think about diet but now reminded I’ll give it a try.
A big trigger for me is alcohol… Just a couple of drinks can make me need the blue inhaler ...