Is "~ is a real thing" a common expression? What does it mean?

Native speaker’s answer
Rebecca
"(Something) is a real thing" is not a very common expression, but is an expression some native English speakers use. This expression means "this thing exists (in my opinion), even if some people are doubtful that it exists". Ex: Heartbreak is a real thing, it is okay to feel sad after a breakup. Ex: Aliens are a real thing, I saw one myself.