I once attended a "dead serious" meeting (as a then young assistant, with my mentor, a widely acknowledged nutritional specialist). The topic went slightly sideways like "how do we survive these terrible additives etc. in our diet". I couldn't tame my inner mischief and asked, with my best pokerface: "we even live longer than without - so maybe we are conservated, like the mummys in Egypt, only alive"? Instead of laughing, they started to seriously discuss it...

After 5 minutes or so, "my" prof said, let us flee, before they get the joke, and they will...