None of those girls in the video Rooter posted have got any surplus fat on them at all. It is just a (and their) normal body shape.

And they are all fit and athletic! The song is just as a much a confection as what they were eating. It's 4 and half minute running time was another big table of confection. I started to lose my sanity by the 2 minute mark, and I only salvaged it by bailing out a minute later!