Towards the end of the film, she revealed that her distaste for carbs stemmed from celiac -- not because she was an L.A. low-carb snob. Rah!
However -- not to be too picky; I mean, just the mention of celiac disease in a mainstream film is a giant step forward -- but she referred to an allergy to gluten, whereas we know that celiac is a total intolerance that is not IgE-mediated, as is an allergy. (Image above is unrelated to the Hallmark movie.)
What other gluten free characters have you seen in films/television?