Chocolate is an antidepressant, which is especially useful as you start to gain weight.

The line is a compact joke built on a self-reinforcing cycle: chocolate is framed as a mood-lifter (“antidepressant”), yet its comforting use is paired with an unwanted side effect (weight gain). The punchline turns that side effect into the very reason the “antidepressant” becomes “especially useful,” implying that the guilt or dissatisfaction from gaining weight creates more need for comfort. Beneath the humor is a familiar modern tension between indulgence and self-image, and a satirical nod to how people rationalize treats as self-care while ignoring (or laughing at) the consequences.