Hi, I hadn't heard that before but it wouldn't surprise me. It is a lovely herb and seems to grow near people who need it. I had not heard of it until I was diagnosed with Bronchiectasis the same year we moved into a house in Canada that had tons of it growing in the back yard. I discovered the plant first and about 3 months later got my diagnosis. I have used the liquid tincture also but don't find it to be mucus producing. I use the tincture because it is supposed to nourish the lungs generally like salmon and garlic, etc.