According to Patricia Arquette, one of the producers of the show asked her to lose some weight. Arquette refused, arguing her character had three children and (like Arquette herself) had no problem with her mom-look.
Sofia Vassilieva missed a few episodes in season 5 because she was shooting Ma vie pour la tienne (2009). She had to shave her head for the role and Patricia Arquette supported her by doing the same, which explains why the two of them had short hair at the beginning of season 6.
The names "Harlow" and "Enzo," spelled out in refrigerator magnets, can be seen on the DuBois refrigerator. These are the names of Patricia Arquette's real-life children.
The show was cancelled after five seasons by NBC, but it was soon picked up by CBS, on which the show ran for two more seasons and had the chance to wrap things up.
The real Allison DuBois served as a consultant to the show.