Sofas and Celebrations (the edible ones that is).
They seem to dominate the period between Christmas Day and the Twelfth day of Christmas on January 5th.
If you are not sitting in a sofa watching an advert on ITV for sofas (mainly featuring glamorous models just sitting on sofas), you are "just eating one" Celebration (followed by "just another eight") on a sofa, or all three.
Surely it can't be long before someone conducts a "scientific" survey to prove a link between fag-end Festive season Sofa adverts, Celebrations and a serious UK January obesity spike.
There is certainly a gap in the survey market there, begging to be filled.