In the US, we've had some memorable marketing campaigns for certain generic foods or beverages."Got milk"" and "Behold, the power of cheese" come to mind. A comparable line of commercials in Japan uses the jingle 「牛乳に相談だ」, which is a little difficult to translate directly, but is probably something like "Milk can help."
They tend to advertise that milk can work to enhance attributes like your strength, beauty, or powers of concentration:
This one I saw recently uses its tagline a little more literally. The jingle can also be translated as "Consult with milk." So that is what this girl is doing:
She says that she's been dieting but isn't healthy. And she is told that the milk advises she...drink milk. Word.