Please, no, no more "This is a PEN" Japanese-language chauvinism, I beg you. There is a whole thing in Japan about how the Japanese language has various hidden beneficial qualities, like it's some kind of gift from God. This idea about expelling less air while speaking in Japanese is firmly in that vein, and it got a lot of play on tabloid news shows, and it's total garbage.
So why is it garbage? What do you have to disprove the hypothesis? because I did read it accompanied with measurements that did show that bilingual persons exported less air speaking Japanese vis-à-vis English.
As there is scientific evidence to back up the idea that phonological features of languages affect the spread of diseases:
