Short self deprecating voice lines like this spread on soundboards and in meme edits because they sum up a relatable feeling in under two seconds. The I'm fat clip is shared as a reaction rather than a statement, usually to exaggerate a moment of indulgence for comic effect. Its popularity comes from timing and delivery rather than a known source, and creators reuse it in food challenges, lazy day montages, and gaming streams. The phrase stays searchable as a simple, blunt punchline that needs no setup or context to understand.