I can personally attest to the fact that die off can cause major breathing problems. I had tons of candida in my lungs. I have told this tale many times of during my first large die off, waking up in the middle of the night every night 2 or 3 times gasping for air, and having to go into the bathroom (so as not to disturb sleeping hubby) where I would sit on the edge of the toilet for 45 minutes, coughing and coughing with this foamy white metallic tasting crap spewing out of my lungs, taking puff after puff of my rescue inhaler just so I could breathe enough to go back to sleep for another couple of hours until the whole thing would start again. Those were my horror-show days. Lasted about a month and a half. I had so much candida in my lungs it was ridiculous. Candida will cluster in your weak areas (for instance, I never got skin candida as my skin has always been great, but my lungs, as an asthmatic, have always been a weak point). It does get better - LOTS! Before I had discovered it was candida, I had been feeling short of breath also. And, sometimes with additional die off, the symptoms return but very mildly.