Currently available on 2 streaming services.

South Park: The End of Obesity - watch online: streaming, buy or rent

Currently you are able to watch "South Park: The End of Obesity" streaming on SkyShowtime, Strim.

Cast

Trey Parker
Stan Marsh / Eric Cartman (voice)
Matt Stone
Various Characters (voice)
April Stewart
Various Characters (voice)
Mona Marshall
Sheila Broflovski / Mrs. Tweak / Linda Stotch (voice)
Kimberly Brooks
Laura Tucker / Linda Black (voice)
Jessica Makinson
Additional Voices (voice)
Vernon Chatman
Towelie (voice)
Feraz Ozel Ellahie
Additional Voices (voice)
Betty Boogie Parker
Additional Voices (voice)
Abdullah Saeed
Additional Voices (voice)
Kyle Richards
Self (archive footage) (uncredited)
Oprah Winfrey
Self (archive footage) (uncredited)
Jennifer Howell
Bebe Stevens